Hari Prasad Sharma (Sunil Dutt) and his wife Parvati (Rohini Hattangadi) come from their village to visit their doctor son, Dr. Murli (Sanjay Dutt) in Bombay, who is the head of a charitable hospital. They are greeted with fanfare and are given a tour of the hospital. Hari and Parvati decide that since Murli is well settled, he should get married. So they arrange a marriage with Dr. J.C. Asthana's (Boman Irani) daughter, Suman Chinki Asthana (Gracy Singh), also a doctor. Hari and Parvati get a shock when Dr. Asthana tells them that their son is a fake, a underworld don, is not qualified to be a doctor, leave alone run a hospital, and he is not going to let his daughter marry such a man. Crestfallen, both Hari and Parvati return to their village. Murli alias Munnabhai swears to avenge his parents' humiliation at the hands of Dr. Asthana, by enrolling in the same institution where Dr. Asthana is the dean. Thereafter begins a comical education of an illiterate underworld don - who is all set to change the institution and all it's rules and regulations to suit his goal, and go where no bhai has ever gone before.