Sorghum (Sorghum bicolor L. Moench) is an important food crop in the Ethiopian agriculture. However, the crop’s production is constrained by many biotic and abiotic factors. Amongst Striga hermonthica (Del.) Benth is the most tenacious, prolific and destructive agricultural pests to sorghum crop.This pest is most abundant and damaging on soils of low fertility and nitrogen is an essential element for reversing this effect. Field experiment was conducted during 2008 (2000/01 E.C.) crop growing rainy season Northern Ethiopia to study the productivity response of sorghum varieties to different rates of nitrogen application under naturally Striga infested field. Results showed that application of N-fertilizer at different rates significantly increased plant height, leaf area, leaf area index, panicle length, yield per panicle, 1000 grain weight, grain yield, Stover yield and harvest index over the control.