Hello Deep,

• To fulfill the AIIMS MBBS 2018 eligibility criteria, the candidate must have passed in Physics, Chemistry, Biology, and English. The minimum aggregate of the marks General and OBC candidates need to have scored in Physics, Chemistry, Biology and English in their Class 12 or HSC examination must be 60%.

• Candidates belonging to SC/ST/OPH category should have scored a minimum aggregate of 50% marks in these four subjects in their Class 12 or HSC examination.

Since your PCBE marks is less than 60%. Therefore you are not eligible for it. 

For more information you can refer to this website - https://medicine.careers360.com/articles/aiims-mbbs-eligibility-criteria