ABSTRACT The research to study the effect of dose and frequen- cy of urea fertilizer application on onion yield, had been done in June until September 1996. The research was done in the plastic house at Paponan Village, Parakan District, Temanggung Regency with altitude 990 meters above sea level. The soil type is regosol with pH 6,5. The research uses factorial experiment (3x3) w…