It was established by Father Joseph Breen, the Parish Priest of St Declan's, when Marist College Kogarah could no longer accommodate students from the Penshurst area.

The 2016 Royal Commission into Institutional Responses to Child Sexual Abuse identified two infamous paedophiles, Br Kostka (John) Chute, who was Primary School Principal from 1970 to 1972 and former Science Teacher Robert 'Dolly' Dunn.

Another schoolteacher, Greg Hammond was charged with Historical Child Sexual Abuse, committed during the late 1970s and early 1980s.

In 2006, Mr. Tony Duncan was appointed as the first lay Principal and marked the end of 53 years of Marist leadership at the College.

[citation needed] Important annual events held by Marist Catholic College Penshurst include: Students participate in house competitions including the college swimming, cross country and athletics carnivals.

Accordingly, the college crest and colours were altered slightly and added blue to the original red, green and gold to reflect the co-educational change, while navy replaced the previous red and green stripes with the college name now contained within the bottom of badge of the crest where the stripes previously were instead of in an external banner above the badge on the previous iteration of the college crest.