The invention discloses a preparation method of polyamide wet coating slurry preventing inorganic filler sedimentation. The preparation method particularly comprises the following steps of: (1) taking methanol as a solvent, mixing a filler with poly (sodium 4-styrenesulfonate) solution at room temperature and performing high-speed stirring for 30-50min, and (2) heating a mixed solution in step (1) to 60-70 DEG C, adding calcium chloride and methanol for reaction, stopping stirring after 40-60min, adding a polyamide fiber and allowing polyamide and a methanol-calcium chloride solvent system to perform a complex reaction, beginning stirring when the polyamide fiber is completely dissolved into liquid, and obtaining the polyamide coating slurry with excellent compatibility after 1-2h. The polyamide coating slurry has the high compatibility, while the electric conductivity of a slurry body is also greatly improved, so that the antistatic property of a corresponding coating product is improved.