Aiming at the lightweight structure of Luneburg lens antenna, a mixed structure Luneburg lens design integrated with P-type and I-WP type porous structures is proposed. Firstly, by union Boolean operating of the level set function of P-type and I-WP type porous structures, the mixed structure model is established, and the local interpolation principle is used to ensure the continuity of gradient structure and eliminate the mutation caused by discontinuity. The equivalent permittivity of the basic porous structure is calculated based on the S-parameter inversion method, and the mapping law of the permittivity of the mixed structure with different volume fraction ratio is analyzed. Then the basic porous structure and mixed structure Luneburg lens are designed by discrete method, and three different Luneburg lens antennas are manufactured by 3D printing technology. The focal lengths of Luneburg lenses with different structures are simulated and tested in CST software and in the microwave dark room, and the standard gain horn is selected to feed the lenses. When the focal length is 10 mm, the gains of Luneburg lenses reach the maximum value, and the experimental results are basically consistent with the simulation results. The mixed structure type Luneburg lens has the advantage of light weight while achieving the electromagnetic performance, it reduces the volume fraction by 19.86% compared with the I-WP type and 3.81% compared with the P type, improves the gain of the feed source by about 13 dBi, and has a good convergence effect on the electromagnetic wave emitted by the feed source. The above research may provide theoretical and technical reference for the lightweight design of other types of Luneburg lens antennas.