The strong acaricidal activity of the extract by 90% ethyl alocohol from the Ginkgo biloba L. seeds against Panonychus citri (Mcg.) is reported here for the first time (LC_(50)=48.3mg/L, LC_(90)=94.1mg/L). Furthermore, its yield was 20.4%. While the extract by water showed no acaricidal activity (LC_(50)=5295mg/L, LC_(90)=29139mg/L). Among the soxhlet extractions of the extract by 90% ethyl alocohol, the strong acaricidal activity was only found to be in the non-polar fraction, petroleum ether (b....