Helsingin Suomalainen Yhteiskoulu, commonly abbreviated SYK (English: "Helsinki Finnish co-educational school"), is a private and free elementary, middle and high school in the Etelä-Haaga district of Helsinki, Finland.

Its roots trace back to a group of Finnish intellectuals whose aim was to found a Finnish-language lycée for female students in order to further the education of women in Finland.

SYK is one of the 15 schools in Finland to offer the IB Diploma Programme in the equivalent of the 11th and 12th grades.

Elective fourth language starts in year eight (French, German, Japanese, or Russian[3]), and more are available in the high school.

A typical high school graduate takes the matriculation exam in 2 to 4 foreign languages.