This study was conducted to determine the effect of oak acorn (Quercus castaneifolia) on performance, small intestine morphology, ileal digestibility of nutrient, carcass and some blood parameters in broiler chicks. A total of fifty hundred four one-d old male chickens (Ross308 strain) with seven treatments and four replicates in each treatment were used. Experimental diets were: control (corn-soybean meal diet), raw oak acorn at the levels of 10 and 20 percent, soaked oak acorn diet containing 10 and 20 percent oak acorn soaked in water for 24h., diets contain 10 and 20 percent of soaked oak acorn soaked in water for 48h with twice water substitution. Experiment lasted from 1 to 42 day of ages. Results showed that body weight, weight gain, feed intake, feed conversion ratio, ileal dry matter and protein digestibility, and small intestine morphology was significantly (P