Olchfa School (Welsh: Ysgol Gyfun yr Olchfa) is the largest secondary school in Swansea, South Wales, with approximately 1,700 pupils, including 357 in the Sixth Form.

Olchfa (part of the Sketty Swansea suburb) means 'washing place' in the English language.

Nearly a quarter of pupils come from an ethnic minority background and just over 20% speak English as an additional language.

[1] In the same year, the school reported a GCSE pass rate of 85% (based on 5 GCSEs, grades A*-C), placing it in the top five schools in Wales, top three in Wales for the percentage of A*-A grades[3] and 74th in the UK taking A-levels (A*-B) and GCSE's (A*-C) into account.

The school also consists of smaller demountable classrooms throughout the plot that teach a variety of subjects, an on-site swimming pool and numerous Tennis, Rugby, Football, Netball and Cricket pitches.