For high power gas and chemical laser,a new type of aerodynamic window jet injecting aerodynamic window(JIAW) is proposed. In order to realize the influence of the jet injection on optical quality and the application possibility of the JIAW,the optical quality is measured with the Hartmann diagnostic apparatus. With the test, the optical characteristics of the JIAW under different throat area of the jet injecting nozzle and the stagnation pressure of the jet are presented. The results show that, the JIAW can promise a good optical quality at present experiment conditions except the condition of dH=2.5mm and stagnation pressure of 0.5MPa.