Abstract: Using natural product in poultry nutrition has lately been increased. This study was conducted to evaluate the effect of adding different dietary levels (0.0, 1.0, 2.0 and 4.0%) of Black Cumin Seed (BCS) on productive performance of layer hens over an 8-week trial period. Two hundred 52 week old Hysex laying hens with similar body weight and laying rate were randomly distributed among 4 treatments with 5 replicates with 10 hens each. Results showed that body weight gain for hens fed a layer diet containing 2.0% BCS was significantly lower than those fed 1.0% BCS. Feed consumption was significantly lower for hens fed a layer diet containing 4.0% BCS than those fed both 0.0 and 2.0% BCS. Feed conversion ratio was significantly better for hens fed a layer diet containing 4.0% BCS than those fed both 0.0 and 1.0% BCS. Egg weight per hen increased significantly for hens fed a layer diet containing 4.0% BCS compared to those fed 1.0% BCS. Hens fed a layer diet containing 2.0 and 4.0% BCS showed significantly darker egg yolk color than those fed both 0.0 and 1.0% BCS. It was concluded that adding BCS into layer diets up to 4.0% could improve the productive performance of laying hens in respect to feed consumption, feed conversion ratio and egg weight.