The school is widely known by its initials, SJI and the students of St. John's Institution bear the name Johannians.

While it is commonly thought that the school is named after Jean-Baptiste de la Salle, the founder of the De La Salle Christian Brothers Order and also known as the Patron Saint of Teachers, the school actually takes its name from St. John the Evangelist Church which sponsors their surrounding parish which is also located nearby on Jalan Bukit Nanas.

[4] The La Sallian Brothers and the Board of Governors still hold much more autonomy over the management of the secondary school compared to the Malaysian Ministry of Education.

While the Convent Bukit Nanas, an Infant Jesus Sisters' school for the girls, the AIA building, and the Archdiocese of Kuala Lumpur are located further down the road.

Under the administration of Mr. Leong Kum Loy, St. John has been declared a Heritage Site by the Malaysian government.

Note3: The administration of this school has been continued until now by Mr. Ravi Chandran a/l Krishnan, the sixth principal of SJI who has started serving from the middle of June 2022.

St. John's has several activities and sports clubs that are open to all students, including rugby, archery, soccer, hockey, badminton, sepak takraw, gymnastics, fencing, and others.

Today the members continues their passion through the formation of the Alumni Band, mainly Pipe and Drums, performing at private functions.