Resin composite and method for producing resin composite

A method for producing a resin composite, said method being for producing a resin composite comprising:

• a core material comprising a resin expanded body;
• and a fiber-reinforced resin material comprising a resin and fibers, a surface of said core material being covered by said fiber-reinforced resin material, wherein said core material of said produced resin composite is provided with a corner section, via which one site and another site adjoin each other in the surface at an inner angle of less than 180 degrees in a surface covered by said fiber-reinforced resin material, a first step of producing a pre-molded article by laminating said fiber-reinforced resin material on the surface of said core material and a second step of thermobonding said core material and said fiber-reinforced resin material by pressurizing with a molding die said pre-molded article in a heated state are carried out, a core material including a blowing agent in at least said sites becoming said corner section is used in the second step, and a size of cells in said sites of said core material is increased by said second step, and said core material has a flatness ratio of cells of 20% or more from a surface of said corner section to a depth of 2.5 mm.