The Heinrich-von-Gagern-Gymnasium is a humanistic or classical Gymnasium in the borough Ostend of Frankfurt am Main, Germany. The eponym is Heinrich von Gagern (1799–1880). The school has approximately 1000 students. The Heinrich von Gagern Gymnasium is one of only two schools in Frankfurt which teach Latin and ancient Greek. The other school which offers a traditional, humanist education in Frankfurt is the Lessing-Gymnasium, Frankfurt.