San Dionisio Elementary School was first named Paranaque Elementary School Unit I ( PES I ) founded in 1961. The lot was owned by Santiago Family and rented by the local government to be a school. It was then located at Quirino Avenue San Dionisio, Paranaque with a two- story building having 16 classrooms and 12 teachers with Dr. Norma Abracia as the first principal, now retired City Schools Division Superintendent in Caloocan.
On September, 1992 the contract lease expired and the said school was relocated within the compound of Paranaque Elementary School Central with a new building constructed by the local government of Paranaque carrying the same name. The name PES I was changed to San Dionisio Elementary School when Honorable Councilor Fe Factor of District I passed an Ordinance No. 99-08 and was approved by the Sangguniang Panlungsod on January 26, 1999 to have its own identity because some schools are also using the same name.
Due to an increase of population, a three-story building was again constructed with 9 classrooms thru the effort of Hon. Joey P. Marquez. On July 27, 2006, Jaime Ferrer Building with 11 classrooms got burned leaving the school with only one building ( JPM ). On May, 2007, the construction of a three-story, 12-classroom, new building started to replace the burned building. On February 14, 2008, the new building was inaugurated with 7 classrooms and the other classrooms for completion.
SDES was headed by different principals who were then promoted and transferred to another school.
At present, the school has 2 buildings with 20 Instructional classrooms and 4 Non- Instructional rooms, 52 teaching personnel and 16 non- teaching personnel with Cecilia P. Pablo as the principal.
From that time on up to present, the school produces excellent pupils and always aiming to give quality education.