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Better Education. Brighter Future.


  • TRINITY CATHOLIC: Better Education. Brighter Future. 
  • Normal office hours are in effect. We are here to assist Monday through Friday 7:30 am to 3 pm.
  • Register for Virtual High School Night HERE
  • Lights, Camera, Virtual Auction October 24th - More Information
  • Covid-19 Information

Welcome to Trinity Catholic High School

Trinity Catholic High School, founded on the proud traditions of Mercy, St. Thomas Aquinas, Roasry and St. Thomas Aquinas-Mercy High Schools, is a co-educational, college preparatory high school serving North Saint Louis County and the surrounding areas. It's quality academic program is unmatched in value and recognized the uniqueness and diversity of each student's talent, intellect, style, and ability. Trinity Catholic students are taught to think critically, live virtuously, and serve joyfully.

students in the hallway posing for a picture
students throwing their caps at graduation celebration
students lighting candles

Good News at Trinity

$4.6 Million

Class of 2020 College Scholarships


Graduation Rate

75 Graduates

Class of 2020


Graduates to Date (includes alumni from Mercy, Rosary, Aquinas, Aquinas-Mercy and Trinity Catholic)

Trinity Calendar