This experiment was conducted to determine the effect of dietary cystine (Cys) on the growth performance and the liver lipid and phospholipid of broiler chicks. Basal diet containing 23% CP (TSAA=0.69%) was supplemented with Cys at 0.098, 0.163, 0.238, and 0.324%. Cystine supplementation resulted in significantly (P<0.05) heavier body weights. However, the growth response was not linear nor directly proportional to the level of Cys supplementation. Dietary Cys improve growth but failed to affect abdominal fat and breast meat weights. Cys caused the significantly increase in fatty liver score and liver lipid but a decrease in liver phospholipid. It is clear that Cys resulted in the increase in liver weight. There were positive relationship between liver weight and fatty liver score, and between fatty liver score and liver lipid content.