St. Sebastian's College (Sinhala: සාන්ත සෙබස්තියන් විදුහල, Tamil: செயிண்ட் செபாஸ்டியன் கல்லூரி) is a Catholic educational institution in Moratuwa, Sri Lanka, established in 1854.

The college motto is "Exspecta Dominum Viriliter Age", meaning "Expect the Lord and act manfully" in Latin.

[3] At the request of the Catholics of Moratuwa and the church authorities, the administration of the school was handed over to the De La Salle Brothers on 3 January 1926.

The main school was situated at Uswatte Circular Road, opposite the engine shed of the Moratuwa Railway Station.

He managed fundraising projects and set up a welfare office to collect funds directly from parents[citation needed].

In 1974 the college faced another financial crisis and the president's counsel Eardley Perera formed the welfare society.

In 1989 principal, Brother Granville Perera started a large building project for the school and in two years sixteen primary classrooms were built.

In March 1991 Brother Emmanuel Nicholas the Provincial Visitor introduced a Board of Governors as an advisory body to assist the administration of the college.