This research is to study of frequency aplication of water to the yield of soy bean varieties (Vigna unguicu- lata (L) Walp). This research was done from December 28, 1991 until April 20, 1992, at Dumpoh village, Magelang regency. The experiment's site is located 375 meters above sea level, the soil type is Latosol with soil acidity (pH) 7.0. The experiment utilizer was split plot des…