The invention discloses a manufacturing method of a PECVD graphite boat carrier. The manufacturing method comprises the following steps that a impregnated slurry is uniformly coated on the surface ofa semi-finished part of a graphite boat, the semi-finished part is placed in a reaction furnace with a protective atmosphere for high-temperature cracking reaction, the impregnated slurry forms a silicon carbide film layer on the surface of the semi-finished part of the graphite boat, and the finished part of the graphite boat is assembled into the graphite boat. The silicon powder-added polycarbosilane impregnation slurry is cracked at high temperature on the surface of the carbon material of the semi-finished part of the graphite boat, the silicon carbide film layer is formed in situ on thesurface of the carbon material through the interaction of silicon and carbon, and a compact and stable protective layer is formed on the surface of the loose porous carbon material, the protective layer is resistant to high temperature, oxidation and cold and hot impact, the service life of the graphite boat can be prolonged in the production process of the graphite boat, the maintenance time andcost of the graphite boat are reduced, and the production cost of the enterprise is reduced.