Hi Anand,

Which diploma are you talking about? Look, a class 10th certificate is also a diploma. If you talking about that then you are not eligible for 5year LLB as according to the Bar Council Of India, the eligibility criteria for 5year LLB course is the only 10th and 12thqualification suffices with 10th being the basic qualification for seeking admission into the 5-year law course. 

So, you have to do 12th as well.

Also if you are talking about any other diploma after completing your 12th it is irrelevant for pursuing 5 year LLB.

All The Best!