The invention discloses an ionized layer parametric inversion method based on AIS target indication. The method includes the steps of obtaining the target positions and movement information of offshore ships on the basis of the AIS, detecting suspected ship targets on the basis of a sky wave radar echo spectrum and through the combination with the AIS target indication area, conducting correlation, fusion and matching on the ship targets detected by radar and the ships indicated by the AIS so as to obtain the route of a radar ship target group, detecting a quasi parabolic ionized layer model required for the ship target positioning on the basis of sky wave radar backscatter sounding, establishing a mean square error equation of the route of the radar ship target group, and obtaining the optimal solution of the ionized layer parameter on the basis of the optimization solution algorithm. By means of the method, the ionized layer parameter model can be obtained without more professional ionized layer detection devices, and the number of devices and the device cost are reduced. The static and dynamic information of a large number of offshore ships can be provided through a ship automatic identification system in real time, the amount of the information serving as input data of the parametric inversion algorithm is large, the inversion accuracy and stability of the ionized layer parameter are improved, and the spatial resolution of the ionized layer parametric inversion is improved.