diff --git a/tests/Imprink.Application.Tests/UpdateCategoryHandlerUnitTest.cs b/tests/Imprink.Application.Tests/UpdateCategoryHandlerUnitTest.cs
new file mode 100644
index 0000000..3336fe8
--- /dev/null
+++ b/tests/Imprink.Application.Tests/UpdateCategoryHandlerUnitTest.cs
@@ -0,0 +1,244 @@
+using Imprink.Application.Commands.Categories;
+using Imprink.Application.Exceptions;
+using Imprink.Domain.Entities;
+using Imprink.Domain.Repositories;
+using Moq;
+
+namespace Imprink.Application.Tests;
+
+public class UpdateCategoryHandlerTests
+{
+    private readonly Mock<IUnitOfWork> _unitOfWorkMock;
+    private readonly Mock<ICategoryRepository> _categoryRepositoryMock;
+    private readonly UpdateCategoryHandler _handler;
+
+    public UpdateCategoryHandlerTests()
+    {
+        _unitOfWorkMock = new Mock<IUnitOfWork>();
+        _categoryRepositoryMock = new Mock<ICategoryRepository>();
+        
+        _unitOfWorkMock.Setup(x => x.CategoryRepository)
+            .Returns(_categoryRepositoryMock.Object);
+        
+        _handler = new UpdateCategoryHandler(_unitOfWorkMock.Object);
+    }
+
+    [Fact]
+    public async Task Handle_ValidRequest_ShouldUpdateCategoryAndReturnDto()
+    {
+        var categoryId = Guid.NewGuid();
+        var parentCategoryId = Guid.NewGuid();
+        var createdAt = DateTime.UtcNow.AddDays(-10);
+        var modifiedAt = DateTime.UtcNow;
+
+        var existingCategory = new Category
+        {
+            Id = categoryId,
+            Name = "Old Name",
+            Description = "Old Description",
+            ImageUrl = "old-image.jpg",
+            SortOrder = 1,
+            IsActive = true,
+            ParentCategoryId = null,
+            CreatedAt = createdAt,
+            ModifiedAt = createdAt
+        };
+
+        var updatedCategory = new Category
+        {
+            Id = categoryId,
+            Name = "New Name",
+            Description = "New Description",
+            ImageUrl = "new-image.jpg",
+            SortOrder = 2,
+            IsActive = false,
+            ParentCategoryId = parentCategoryId,
+            CreatedAt = createdAt,
+            ModifiedAt = modifiedAt
+        };
+
+        var command = new UpdateCategoryCommand
+        {
+            Id = categoryId,
+            Name = "New Name",
+            Description = "New Description",
+            ImageUrl = "new-image.jpg",
+            SortOrder = 2,
+            IsActive = false,
+            ParentCategoryId = parentCategoryId
+        };
+
+        _categoryRepositoryMock
+            .Setup(x => x.GetByIdAsync(categoryId, It.IsAny<CancellationToken>()))
+            .ReturnsAsync(existingCategory);
+
+        _categoryRepositoryMock
+            .Setup(x => x.UpdateAsync(It.IsAny<Category>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(updatedCategory);
+
+        var result = await _handler.Handle(command, CancellationToken.None);
+
+        Assert.NotNull(result);
+        Assert.Equal(categoryId, result.Id);
+        Assert.Equal("New Name", result.Name);
+        Assert.Equal("New Description", result.Description);
+        Assert.Equal("new-image.jpg", result.ImageUrl);
+        Assert.Equal(2, result.SortOrder);
+        Assert.False(result.IsActive);
+        Assert.Equal(parentCategoryId, result.ParentCategoryId);
+        Assert.Equal(createdAt, result.CreatedAt);
+        Assert.Equal(modifiedAt, result.ModifiedAt);
+
+        _unitOfWorkMock.Verify(x => x.BeginTransactionAsync(It.IsAny<CancellationToken>()), Times.Once);
+        _unitOfWorkMock.Verify(x => x.CommitTransactionAsync(It.IsAny<CancellationToken>()), Times.Once);
+        _unitOfWorkMock.Verify(x => x.RollbackTransactionAsync(It.IsAny<CancellationToken>()), Times.Never);
+        
+        _categoryRepositoryMock.Verify(x => x.GetByIdAsync(categoryId, It.IsAny<CancellationToken>()), Times.Once);
+        _categoryRepositoryMock.Verify(x => x.UpdateAsync(It.IsAny<Category>(), It.IsAny<CancellationToken>()), Times.Once);
+    }
+
+    [Fact]
+    public async Task Handle_CategoryNotFound_ShouldThrowNotFoundException()
+    {
+        // Arrange
+        var categoryId = Guid.NewGuid();
+        var command = new UpdateCategoryCommand
+        {
+            Id = categoryId,
+            Name = "Test Name",
+            Description = "Test Description",
+            SortOrder = 1,
+            IsActive = true
+        };
+
+        _categoryRepositoryMock
+            .Setup(x => x.GetByIdAsync(categoryId, It.IsAny<CancellationToken>()))
+            .ReturnsAsync((Category?)null);
+
+        var exception = await Assert.ThrowsAsync<NotFoundException>(
+            () => _handler.Handle(command, CancellationToken.None));
+
+        Assert.Equal($"Category with ID {categoryId} not found.", exception.Message);
+
+        _unitOfWorkMock.Verify(x => x.BeginTransactionAsync(It.IsAny<CancellationToken>()), Times.Once);
+        _unitOfWorkMock.Verify(x => x.RollbackTransactionAsync(It.IsAny<CancellationToken>()), Times.Once);
+        _unitOfWorkMock.Verify(x => x.CommitTransactionAsync(It.IsAny<CancellationToken>()), Times.Never);
+        
+        _categoryRepositoryMock.Verify(x => x.UpdateAsync(It.IsAny<Category>(), It.IsAny<CancellationToken>()), Times.Never);
+    }
+
+    [Fact]
+    public async Task Handle_UpdateThrowsException_ShouldRollbackTransactionAndRethrow()
+    {
+        var categoryId = Guid.NewGuid();
+        var existingCategory = new Category
+        {
+            Id = categoryId,
+            Name = "Existing Name",
+            Description = "Existing Description",
+            SortOrder = 1,
+            IsActive = true
+        };
+
+        var command = new UpdateCategoryCommand
+        {
+            Id = categoryId,
+            Name = "New Name",
+            Description = "New Description",
+            SortOrder = 2,
+            IsActive = false
+        };
+
+        var expectedException = new InvalidOperationException("Database error");
+
+        _categoryRepositoryMock
+            .Setup(x => x.GetByIdAsync(categoryId, It.IsAny<CancellationToken>()))
+            .ReturnsAsync(existingCategory);
+
+        _categoryRepositoryMock
+            .Setup(x => x.UpdateAsync(It.IsAny<Category>(), It.IsAny<CancellationToken>()))
+            .ThrowsAsync(expectedException);
+
+        var thrownException = await Assert.ThrowsAsync<InvalidOperationException>(
+            () => _handler.Handle(command, CancellationToken.None));
+
+        Assert.Same(expectedException, thrownException);
+
+        _unitOfWorkMock.Verify(x => x.BeginTransactionAsync(It.IsAny<CancellationToken>()), Times.Once);
+        _unitOfWorkMock.Verify(x => x.RollbackTransactionAsync(It.IsAny<CancellationToken>()), Times.Once);
+        _unitOfWorkMock.Verify(x => x.CommitTransactionAsync(It.IsAny<CancellationToken>()), Times.Never);
+    }
+
+    [Fact]
+    public async Task Handle_CategoryWithNullableFields_ShouldHandleNullValues()
+    {
+        // Arrange
+        var categoryId = Guid.NewGuid();
+        var createdAt = DateTime.UtcNow.AddDays(-5);
+        var modifiedAt = DateTime.UtcNow;
+
+        var existingCategory = new Category
+        {
+            Id = categoryId,
+            Name = "Test Category",
+            Description = "Test Description",
+            ImageUrl = "test-image.jpg",
+            SortOrder = 1,
+            IsActive = true,
+            ParentCategoryId = Guid.NewGuid(),
+            CreatedAt = createdAt,
+            ModifiedAt = createdAt
+        };
+
+        var updatedCategory = new Category
+        {
+            Id = categoryId,
+            Name = "Updated Category",
+            Description = "Updated Description",
+            ImageUrl = null,
+            SortOrder = 5,
+            IsActive = false,
+            ParentCategoryId = null,
+            CreatedAt = createdAt,
+            ModifiedAt = modifiedAt
+        };
+
+        var command = new UpdateCategoryCommand
+        {
+            Id = categoryId,
+            Name = "Updated Category",
+            Description = "Updated Description",
+            ImageUrl = null,
+            SortOrder = 5,
+            IsActive = false,
+            ParentCategoryId = null
+        };
+
+        _categoryRepositoryMock
+            .Setup(x => x.GetByIdAsync(categoryId, It.IsAny<CancellationToken>()))
+            .ReturnsAsync(existingCategory);
+
+        _categoryRepositoryMock
+            .Setup(x => x.UpdateAsync(It.IsAny<Category>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(updatedCategory);
+
+        // Act
+        var result = await _handler.Handle(command, CancellationToken.None);
+
+        // Assert
+        Assert.NotNull(result);
+        Assert.Equal(categoryId, result.Id);
+        Assert.Equal("Updated Category", result.Name);
+        Assert.Equal("Updated Description", result.Description);
+        Assert.Null(result.ImageUrl);
+        Assert.Equal(5, result.SortOrder);
+        Assert.False(result.IsActive);
+        Assert.Null(result.ParentCategoryId);
+        Assert.Equal(createdAt, result.CreatedAt);
+        Assert.Equal(modifiedAt, result.ModifiedAt);
+
+        _unitOfWorkMock.Verify(x => x.BeginTransactionAsync(It.IsAny<CancellationToken>()), Times.Once);
+        _unitOfWorkMock.Verify(x => x.CommitTransactionAsync(It.IsAny<CancellationToken>()), Times.Once);
+        _unitOfWorkMock.Verify(x => x.RollbackTransactionAsync(It.IsAny<CancellationToken>()), Times.Never);
+    }
+}
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