St. Paul's College Alumni Association was established in 1920. There was no official name by the time it was established. By 1930, It was recorded that more than 100 alumni and the management of school was in a restaurant in the Sheung Wan to discuss the establishment of "Old Pauline Union", followed by students in Guangzhou and Shanghai and other places setting up a branch with a view to contacting alumni. During the Japanese occupation of Hong Kong, Macao was the temporarily place where alumni gatherings took place. Until 1950, the Bonham Road school complex was completed, students were to be given a formal name for the "St. Paul's College Alumni Association" (SPCAA). The role of the SPCAA had also changed, been taking a leading role in addition to serve merely as the links between the alumni, the SPCAA will also continue to maintain contact with the school, there are four alumni representative in the College Council, together for the deliberations in school affairs.