The invention concerns a supported metal catalyst based on at least one metal selected in the group M consisting of palladium, platinum, ruthenium, rhodium, iridium, holmium, osmium and gold, used for directly making hydrogen peroxide from hydrogen and oxygen. The invention also concerns a method for making said catalyst comprising successively an impregnating step with a solution based on one or several salt(s) of at least one metal of group M on a support, and a reduction step characterised in that at the end of the reduction step, the catalyst is treated with an aqueous acid solution comprising bromine and bromide ions. The catalyst is characterised by metal or crystallised metal aggregates with size ranging between 0.1 and 20 microns and preferably between 0.1 and 10 microns. The supported bimetal catalyst is preferred, for example Pd—Pt, Au—Pt, Pd—Ho and Pd—Au.