The Eta Sigma chapter was chartered on the campus San Diego State University on Saturday, January 1, 1972 becoming the 370th house of Alpha Phi Alpha Fraternity Incorporated. The University of San Diego (UCSD) was added September 9, 1972.

The chapter has rich history of leadership and civic engagement through the campus and surrounding community. Prominent brothers of the chapter have held position in ASU, Black Student Union (BSU), and the National Panhellenic Council (NPHC) to name a few.

The Eta Sigma chapter’s charter was later expanded granting the chapter greater reach and greater influence within the colleges and universities in the greater San Diego area to include University of California, San Diego (UCSD), University of San Diego, and California State University, San Marcos.