Colegio De San Lorenzo (also called CDSL or colloquially, SanLo) is a Catholic educational institution in the Philippines located in Congressional Avenue, Barangay Bahay Toro, Quezon City and in Macabebe, Pampanga. Students of Colegio De San Lorenzo are known as Ruizians.

The school’s founders, Cirilo Lloyd V. Balgan and Annette F. Balgan, envisioned an educational institution that will respond to the Church’s call for the laity’s greater participation and involvement in the educational apostolate. In 1988, they established CDSL as an educational institution dedicated to the total formation of the Catholic Filipino youth who, like San Lorenzo Ruiz de Manila, will live their lives in the service of God.

On the 18th of October 1987, as Lorenzo Ruiz de Manila’s canonization rites at St. Peter’s Basilica in Rome began, the cornerstone laying ceremonies of CDSL in Quezon City solemnly proceeded. The founders dedicated the school to San Lorenzo Ruiz de Manila to honor and perpetuate the memory of the first Filipino saint, and to let the youth emulate the virtues that led to his sainthood.

During the initial year, 1988 to 1989, the school building was a two-story edifice with 14 rooms. Twelve of these rooms were used as classrooms, one as an administrative office, and another for student services. The construction of a three-story wing facing Jupiter Street began in the summer of 1989, envisioning its additional 15 additional classrooms to meet the needs of an increasing student population for the next two school years. The ten-classroom two-story building fronting Congressional Avenue saw not only the completion of the student services facilities, but also the development of the adjacent lot for a separate wing for pre-school and primary level pupils.

In 1992, plans were made to open the college department. Although faced with great difficulties in putting up a tertiary level, the founders did not waver. The trials they faced even gave them greater resolve to push through with the opening of the college. The Commission on Higher Education (CHED) finally gave its approval for the college department to open in school year 1993 to 1994, with Dr. Enrique F. Coralejo as the first college president and the late Professor Raymundo Briones as the first college dean. The first batch of college graduates proudly marched on March 1997.

Dr. Rogelio Lota was appointed dean from 2002 to 2004. Along with the continuous efforts to improve the curriculum of each college program, he emphasized the importance of extracurricular activities. His term as dean was marked with numerous school events which highlighted the talents and capabilities of the students. Such activities contributed to the achievement of holistic development.

The year 2011 marked a significant milestone in the history of the college department, welcoming Dr. Pedro R. Lora, Jr. as the College Executive Director. His leadership is anchored on the core values of Faith, Excellence, and Service, thus his appointment led to significant changes in the college department. In his first year, enrollment grew 120 percent from the previous school year with the introduction of new academic programs. Through his leadership, the college moved to greater heights in providing affordable quality education.

In the same academic year, Colegio De San Lorenzo responded to the surge in student population by providing a more diverse selection of programs for its students. The College reopened two programs, Bachelor of Science in Psychology and Bachelor of Science in Computer Science, and introduced a new program, Bachelor of Science in Tourism Management.