Oloolaiser High Sch is a government boys’ boarding secondary school in Ngong, Ngong Township Sub location, Ngong Location, Ngong Division, Kajiado North Constituency in Kajiado.

The school was established in 1967 and opened by the first president of the Republic of Kenya, Mzee Jomo Kenyatta as a harambee day mixed secondary school in the early 1970s. The present day Oloolaiser High School has grown and expanded exponentially to a three stream boarding boys only high school.The school stands on a 38 piece acre land with 640 students and 32.students.

The High School has prided itself in producing alumni who have ended up being notable leaders and pacesetters in their various fields in Kenya and beyond by offering uniquely competitive subjects that give their alumni that upper hand over learners from other schools.