This study was conducted at 8 different stations in Çemişgezek fishing cooperative area of Ke-ban Dam Lake from September 2004 to April 2006. In study. in order to determine fish catch-ing efficiency of colored gillnets with 55 mm mesh size in Keban Dam Lake and to stained green, blue, red, black color from this mesh sizes, 4 different color nets with hanging ratio of 0.50 and 0.67 from each mesh sizes seperate to equip 8 number nets were used. During two years study period, in total 427 fish were caught; of these 245 with hanging ratio of 0.50 and 182 with hanging ratio of 0.67 with monofilament gill nets. According to hanging ratio, mesh size and color, of nets total lenght and weight measured of these avarege and standart error were calculated. Therefore, Chi-square analyesis was used in compare this fishes. In this study was determined that different colors of material effect on catch efficiency in gill nets. Nets with 0.50 hanging ratio and 55 total mesh size catched B. rajanorum mystaceus and C. trutta. Blue color net with 0.67 hanging ratio and 55 mm mesh size catced morely B. esocinus and B. xan-thopterus. The results showed that material of different colors is effective on gillnets and it should be black, red, green and blue gill nets for black fish. Carp, earring fish and barbel fish respectively in Çemişgezek area of Keban Dam Lake.