Hii Aspirant, There are several types of diploma computer science so, 

1. Diploma in Computer Science and Engineering – 3 years

2. Diploma in Computer Engineering – 3 years

3. Diploma in Software Engineering – 3 years

4. Diploma in Computer Technology – 3 years

5. Diploma in Computer Hardware Technology – 3 years. 

I hope your doubt is cleared still if you have any then free to comment.