For the complexity of aerospace project development, its risk evaluating model was proposed on the basis of modern multiple attribute linguistic decision method. The method of decision based on uncertain extended ordered weighed averaging (UEOWA) operator was given under incomplete linguistic information. The scale of risk measure was extended, on the one hand which can measure accurately the risk, on the other hand which can match with linguistic information of decision model in reason. The example of risk decision for aerospace project development was presented to show the feasibility and effectiveness of this method. It can offer a new method for the evaluation of project risk.