An oxygen reduction catalyst which includes composite particles including a portion including an inorganic metal compound and a portion containing carbon. The composite particles include a metal element M1, carbon, and oxygen as constituent elements; the amount of carbon atoms is 1 to 10 mol, and the amount of oxygen atoms is 1 to 3 mol, assuming that the total amount of atoms in the metal element M1 is 1 mol; a G-band and a D-band are present in a Raman spectrum, and a V/G ratio defined in an expression described below is 0.10 to 0.35: V/G ratio=(minimum value of spectral intensity in region V which is a region between G-band and D-band)/(peak intensity in G-band).