In contrast to conventional solid-phase sintering, molten salt method can provide a fast mass transfer and nucleation process at lower temperatures which has potential to synthesize the ceramic solid solution for immobilization of high-level nuclear waste (HLW). In this work, Nd-doped zircon (ZrSiO₄) ceramics (Zr_1-xNd_xSiO_4-x/2 (0≤x≤0.1)) were prepared by the molten salt synthesis(MSS) at different sintering temperatures (1100, 1200, 1300, 1400, 1500 ℃) for different sintering time (3, 6, 9, 12, and 15 h). Chemical stability of Nd-doped zircon ceramics in simulated geological disposal environment was studied by static leaching test (PCT). Zr_1-xNd_xSiO_4-x/2 was synthesized by the molten salt method under the optimum molar ratio of molten salt to oxide at 10:1, sintering temperature at 1200 ℃ and sintering time of 6 h with the solid solution of Nd in ZrSiO₄ being increased to 8% (in mol). The MSS can reduce the synthetic temperature, shorten the sintering time and save the solid solution. The immobilizing mechanism of ZrSiO₄ ceramics for trivalent actinide nuclides is lattice immobilizing. Experimental results show that the normalized leaching rate (LR_Nd) of Nd is as low as ~10^-5 g·m^-2·d^-1. ZrSiO₄ ceramics have no phase evolution before and after leaching, suggesting good structural stability. TLeaching model consolidates that Nd leaching is due to dissolution of the ceramic surface layer. Data from this study show that MSS is a promising method to synthesize ceramics solid solution.