In order to study susceptibility and tolerance of rapessed cultivars (Brasica napus L.) under limited irrigation condition in 2005 and farm of seed and plant improvement research institute an experiment was conducted in form split plot design based on complete block design with four replications. Irrigation as main factor in two levels (Normal irrigation, after 80 mm evaporated water from class A evaporation pan and limited irrigation, stop irrigated after stem elongation stage) and rapeseed cultivars in twenty levels as sub factor. The results showed that irrigation had significant effect on 1000 seed weight, number of pods in plant, seed number in pods, seed yield, biological yield, harvest index and oil yield. In limited irrigation seed yield, biologic yield, harvest index and seed oil yield respectively decreased 42, 16, 23 and 50 percent compared to normal irrigation. Plant height, branch, pod number in main stem and pod number in branch had significant and positive correlation with seed and biologic yield.