A manufacturing method of a liquid supply component in which a liquid supply path is formed between a first constituent component and a second constituent component that are joined with molten resin. The method includes a first step of preparing these constituent components, a second step of causing the constituent components to face each other and forming an orifice portion and a reservoir portion between a mold and a surface of either of the constituent components, and a third step of pouring the molten resin between the constituent components so that it flows into the reservoir portion through the orifice portion.

An orifice portion and a reservoir portion are formed between a mold and a surface of either of a second constituent component and second constituent component. Molten resin flowing from between a first constituent component and the second constituent component flows into the reservoir portion through the orifice portion.