Born in Ceylon, he was educated at the Colombo Academy and at the University of London. He taught at S. Thomas' College, Mt Lavinia, before becoming a senior master of Royal College Colombo. With the retirement of Principle Lionel.H.W. Sampson, Wijesinghe was appointed as acting Principal of Royal College in 1938 to 1939 until the arrival of E.L. Bradby who became the last British principal of the college. In 1938, Wijesinghe was able to gain the Maligawa town house of Sir James Obeyesekere as the hostel of the school, since for over 80 the school did not have a hostel. The H J Wijesinghe Memorial Endowment is awarded at Royal College, Colombo in his memory.