In order to meet the need of multipoint meteorological sounding in the stratosphere,a sounding rocket design scheme of 6 dropsondes that can be sequentially released was carried out.Six-degree-of-freedom ballistic model was established for rocket flight.On the basis of analyzing dropsonde release constraint factors, the key ballistic point parameters under different launch elevation were calculated.It’s shown that the standard trajectory can be planned with the launch elevation angle of 83° under the existing general parameters, which can meet the release requirements of the height, attitude and dynamic pressure, and has the conditions for engineering application.