The invention discloses a manufacturing process method for a trench metal oxide semiconductor (MOS). The method comprises the following steps of: (1) after finishing P-type implant and diffusion of a conventional trench MOS process, growing a linear oxidation layer and silicon nitride serving as a hard mask layer in turn; (2) photoetching and etching the hard mask layer to define a trench and an N-type source ion implantation area; (3) forming a tetraethyl orthosilicate (TEOS) oxide layer by chemical vapor deposition; (4) performing back-etching on the TEOS oxide layer and forming a spacer onthe side wall of the hard mask layer; (5) etching the trench; (6) removing the spacer by wet etching; (7) performing thermal oxide growth to form a gate oxide layer and a gate polysilicon filled trench, and performing gate oxide layer back-etching; (8) performing N-type source ion implantation by utilizing self-alignment of the hard mask layer; (9) removing the hard mask layer and the gate oxide layer on the N-type ion implantation area by wet etching; and (10) performing a subsequent process which is the same as a conventional process. The method does not need a source mask and a corresponding photoetching step, thereby simplifying a process flow and saving cost compared with the conventional process.