Padmasiri Thrimawithana was born on 29th February 1964 as the eldest of a family striving hard with economic difficulties in Galle district. He has completed secondary education in Mahinda College Galle and gained entrance to the Colombo Medical Faculty in 1985/86.

The issues related to the first private medical college in Sri Lanka created in 1981 through the blessings of the then ruling party were rising to the peak during this period. The whole university system was going through a series of troubles and in mid 1987 it became standstill.

For the first time in Sri Lankan history, the whole university system was functionless from mid 1987 to early 1990. "Threema" as popularly known among his colleagues, soon realized that he has to contribute to another mission before achieving the primary medical degree. He took part actively in the students struggle against the private medical college and dedicated his life for the protection and upliftment of free education system in Sri Lanka. He was abducted killed and surreptitiously disposed in October 1988.