In 1984, the Holy Trinity Preschool started with 28 children in the family home of the Albanos with Gertrudes as the school head and Rosalyn as the teacher.

Josemar Albano allowed the construction of a new building for the primary grades while the original preschool structure was renovated.

SY 1989-1990, the school acquired legal personality as Holy Trinity College of General Santos City Inc. when it was registered with the SEC on May 21, 1990.

The school continued to add more college courses to its program offering more learning and job opportunities for the local population.

In 1996, a new four-story building was constructed to accommodate the Basic Education students and to allow for the creation of many facilities including the library and laboratories.

In accordance with CHED Memo Order #41 Series of 2008, Holy Trinity College of General Santos has been recognized by the Institutional Quality Assurance through Monitoring and Evaluation (IQuAME) of the Commission on Higher Education (Philippines) (CHED) as a Developing Institution in the Philippines.