A method for manufacturing a composite of metal and resin, comprising: a shaping step of shaping a pure titanium-based type alloy substrate by mechanical working, a surface treatment step including chemical etching by immersing said shaped sub-strate in an aqueous solution containing ammonium monohydrodifluoride and rinsing the same with water for providing the surface of said shaped substrate with an ultrafine texture face in which bent, ridge-like protrusions having a width and height of from 10 to 300 nanometers and a length of from 100 to a few thousand nanometers rise up on the surface at a spacing period of from 10 to 300 nanometers in observation with an electron microscope and in which a surface roughness with mean width of profile element (RSm) of 2 to 3 μm at a period of 0,5 to 5 μm and maximum height of roughness profile (Rz) of up to 3 μm is observed with a scanning probe microscope, an insertion step of inserting said substrate that has undergone said surface treatment including chemical etching into a metallic mold for injection molding mold, and an integration step of injecting a first resin composition or a second resin composition onto said inserted substrate and integrating said substrate with said first resin composition or the second resin composition; said first resin composition being one in which a polyphenylene sulfide resin is the main component and a polyolefin resin is an auxiliary component, and said second resin com-position being one in which a polybutylene terephthalate resin is the main component and a polyethylene terephthalate resin and/or a polyolefin resin is an auxiliary component. a shaping step of shaping a pure titanium-based type alloy substrate by mechanical working, a surface treatment step including chemical etching by immersing said shaped sub-strate in an aqueous solution containing ammonium monohydrodifluoride and rinsing the same with water for providing the surface of said shaped substrate with an ultrafine texture face in which bent, ridge-like protrusions having a width and height of from 10 to 300 nanometers and a length of from 100 to a few thousand nanometers rise up on the surface at a spacing period of from 10 to 300 nanometers in observation with an electron microscope and in which a surface roughness with mean width of profile element (RSm) of 2 to 3 μm at a period of 0,5 to 5 μm and maximum height of roughness profile (Rz) of up to 3 μm is observed with a scanning probe microscope, an insertion step of inserting said substrate that has undergone said surface treatment including chemical etching into a metallic mold for injection molding mold, and an integration step of injecting a first resin composition or a second resin composition onto said inserted substrate and integrating said substrate with said first resin composition or the second resin composition; said first resin composition being one in which a polyphenylene sulfide resin is the main component and a polyolefin resin is an auxiliary component, and said second resin com-position being one in which a polybutylene terephthalate resin is the main component and a polyethylene terephthalate resin and/or a polyolefin resin is an auxiliary component.