Thewarapperuma, known for his active involvement in politics, served as a Member of Parliament for the UNP. His sudden and untimely demise has saddened many, and tributes are pouring in for the late parliamentarian.
He was given the position of Deputy Minister of Internal Affairs, Wayamba Development and Cultural Affairs in the United National Party led national government in 2015.
In July 2016, Palitha Theewarapperuma went on hunger strike demanding authorities to admit 9 children in to a public school. During the events he attempted suicide by hanging himself. However he was admitted to the hospital and underwent a bypass surgery. Following the incident the students were admitted to grade 1 of the school.
During the 2020 COVID-19 pandemic he on several occasions he distributed food supplies to the people of the village Atalugama, which was under lock down due to COVID infections.
Palitha Thewarapperuma has been popular amongst the local masses for his social service activities and philanthropy. He rose to fame among people of the entire island especially during the COVID-19 pandemic in Sri Lanka for having provided food, dry rations and other necessities to the rural population of constituency the Kalutara Electoral District. >මේ වනවිට එතුමාගේ දේහය කළුතර ශික්ෂණ රෝහලේ තැන්පත් කර තිබෙනවා.