Klang High School was originally named Temporary English School and was open to students in Klang on 14 January 1928 with the beginning of the academic school year. At the beginning, the school conducted the class in a small hut at the current sports field of the school.
The British government could feel the need of English education for the local community in Klang. Thus, after gaining approval from the British central government in Malaya, the school was given better facilities by the British government, particularly the buildings currently named "Block A" and "Block B". The main school block (Block A) was officiated by the Sultan of Selangor on 20 March 1930.
During the World War II, in 1941, the Klang High School was used by the British as the headquarters of the Medical Auxiliary Service for Klang. There were two doctors assisted by 52 nurses. However, the school went into ruin when the Japanese army invaded Klang. Innocent civilians serving the school were killed by the Japanese army and the school's facilities were damaged during the war. During the Japanese invasion, the school was used as a military base and also as medical camp. The school reopened after World War II having been used as a military hospital by the British Military Authority and the Japanese army.
After Malaysia's independence, it was known as Sekolah Tinggi Klang or by its acronym STK. By the end of the 1990s, the name was changed in accordance with Ministry of Education regulations to its current name, SMK Tinggi Klang.
The year 2028 will mark the 100th year anniversary since the establishment of the Klang High School in year 1928. The name of the school has been a legend among many generations in Klang and Selangor. A grand celebration is expected in the year 2028. The administration, teachers, students, parents and old boys / alumni will help in organising the grand celebration of its 100th year anniversary that year.