Abstract: The present invention relates to a manufacturing method of quartz substrate of light coupler utilizing quartz rod as basic material, and after a series of mechanical manufacturing procedure including a material selection, tooling positioning, wax fixing, grinding and cutting, and wax melting, it quickly, accurately, and definitely produces an optical fiber fixing groove on the peripheral surface of the selected quartz rod, such that the expected quartz substrate can be formed directly, and it definitely gives a simple, convenient, fast, and high efficient way for producing the quartz substrate of the lighter coupler. Such method is applicable for mass production, meanwhile it is economically cost effective that does not require a second manufacturing for the precision and application convenience, and enhance the productivity for the industry.