The man, Ankit Agarwal, claimed to be an Assistant Professor in the department of general surgery at AIIMS and was caught while trying to enter the doctors' hostel forcibly.
"When the security guards stopped him, he said he was from the faculty and also pulled out an identity card of AIIMS having signature of the chief security officer.
"But the guard became suspicious and further enquiry revealed that the man was not a doctor at all," AIIMS Chief Security Officer R S Rawat said.
The accused was handed over to police who registered a case under IPC sections 468 (forgery for cheating) and 471 (using a forged document as genuine) and arrested him.
"He worked with a pharma company and admitted to have carried the forged identity card of a doctor to gain easy access into AIIMS and park his bike without any trouble," a senior police officer said.
This is second such incident in thr last 20 days. On February 3, another man posing as a doctor was arrested from the institute.