Abstract: A curable resin material-fine particle composite material, an optical material, and a light emitting device are disclosed. The composite material includes a resin material of an uncured or semicured resin and fine particles of an inorganic material dispersed in the resin material. The surface of the fine particles is treated by at least first and second surface treatment agents composed of molecules represented by the formulas (1) and (2), respectively: first surface treatment agent: R1—X1 ??(1) second surface treatment agent: R2—X2 ??(2) wherein R1 represents a long-chain aliphatic or alicyclic hydrocarbon group, R2 represents a hydrocarbon group having a structure showing affinity with at least a portion of monomers composing the resin material, and X1 and X2 independently represent a carboxyl group —COOH, hydrohydroxyphosphoryl group —PH(O)(OH), phosphono group —PO(OH)2, sulfino group —SO(OH), sulfo group —SO2(OH), thiol group —SH, amino group —NH2, or vinyl group —CH?CH.