As you are looking for information about minimum marks to qualify AIIMS MBBS Entrance Exam, so here I am providing information related to pattern:

Exam Mode Computer based test (CBT)
Number of questions 200 multiple choice questions (MCQ)
Exam duration 3 hours and 30 minutes
Language of the question paper English and Hindi
Marking Scheme +1 for correct answer and -1/3 (one third) for incorrect
answer
Syllabus Physics, Biology and Chemistry subjects taught during
HSC/10 +2 level

Exam date: May 28, 2017.

Marking scheme of AIIMS MBBS Entrance Exam:
Question type Marking scheme
Correct response 1
Incorrect response -1/3 (one third)
For review 0
For Not answered 0

Minimum Qualifying Marks:
Category Percentile
General 50
SC/ST 40
OBC 45

Paper Pattern:
Subjects No. Of Questions
Physics 60
Chemistry 60
Biology (Zoology & Botany) 60
General Knowledge 20
Total 200