In the presence of an imide compound (e.g., N-hydroxyphthalimide) shown by the formula (2):wherein R1 and R2 independently represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a cycloalkyl group; or R1 and R2 may bond together to form a double bond or an aromatic or non-aromatic ring; Y is O or OH and n=1 to 3;or the imide compound and a co-catalyst (e.g., a transition metal compound), an adamantane derivative having a functional group such as a nitro group, an amino group, a hydroxyl group, a carboxyl group, a hydroxymethyl group and an isocyanato group is oxidized with oxygen. According to the above method, an adamantane derivative having a hydroxyl group together with a functional group such as a nitro group, an amino group, a hydroxyl group, a carboxyl group, a hydroxymethyl group and an isocyanato group is efficiently obtained.