Hey as per my idea yes thumb impression is required for filling MBBS form
in AIIMS and here I am giving you its details

Requirement

Applicants can fill AIIMS MBBS Application form in online mode only as no
other mode like offline, form.

At the time of online registration candidates have to upload the scanned
photograph, signature and thumb impression


Eligibility criteria
Applicants must have passed 10+2 or its equivalent examination from any recognized Board with English, Physics, Chemistry and Biology as core subjects
Applicants Should have scored a minimum of 60% marks (for General and OBC category) or with 50% marks ( for SC/ ST/ OPH/ Foreign Nationals) in the qualifying exam

Important date
Online Registration of AIIMS MBBS 2016 Application was Began on February 15, 2016
Online Registration of AIIMS MBBS 2016 Application Closed on March 15, 2016 at 05:00 PM
Status of Registration including rejection / deficiencies in application March 30, 2016
Last date for complying with deficiencies in application as indicated April 08, 2016

Address:
All India Institute of Medical Sciences
Ansari Nagar East,
New Delhi,
Delhi 110029
Phone: 011 2658 8500