In order to determine the FCS (flight control system) performances which the WTBVFT (wind tunnel based virtual flight testing) can evaluate, and lay the foundations for designing the WTBVFT evaluation methods, the flight performance indexes and flight quality indexes of FCSs which WTBVFT can perform the work of evaluation were proposed according to the features of WTBVFT; the evaluation capability differences among the WTBVFT, the HILS (hardware-in-the-loop simulation) and the flight tests were compared; the differences of evaluation results between WTBVFT and free flight caused by the features of WTBVFT were analyzed; from the aspects of testing, data processing, and the performance determination, the specific requirements of the WTBVFT evaluation methods for evaluating the above indexes were proposed and the evaluation requirement differences among the WTBVFT, HILS, and flight tests were compared.