A field study was carried out to find out the effective chemical for controlling algae without visual injury on creeping bentgrass golf greens. The results were as follows. 1. Chlorothalonil(75%), Metalaxy(7.5%)+Mancozeb(56%) and Mancozeb(75%) did not injure creeping bentgrass. Only chlorothalonil(75%) effectively controlled algae regardless of concentration among above mentioned 3 fungicides. 2. Mancozeb frequently used on golf courses showed about 50% effect on controling algae in this study. 3. Mancozeb(75%)+Copper hydroxide(73%) and Mancozeb(75%)+Streptomycin(100%) had good effects on algae control while injuring creeping bentgrass. 4. Copper hydroxide(73%) and copper sulfate basic(58%) $includingulcorner$Cu$lrcorner$showed effective algae control but caused injure creeping bentgrass. 5. Streptomycin has been scarcely used on golf greens but streptomycin(20%) 0.1g a.i/$m^2$ had good control of algae and durability without injuring creeping bentgrass.