The present invention relates to a catalyst for wastewater treatment and a method for wet oxidation treatment of wastewater using the catalyst, in particular, the catalyst of the present invention can suitably be used in wet oxidation treatment of wastewater, under high temperature and high pressure conditions. The present invention provides a catalyst for wastewater treatment containing a catalytic active constituent containing at least one kind of an element selected from the group consisting of manganese, cobalt, nickel, cerium, tungsten, copper, silver, gold, platinum, palladium, rhodium, ruthenium and iridium, or a compound thereof, and a carrier constituent containing at least one kind of an element selected from the group consisting of iron, titanium, silicon, aluminum and zirconium, or a compound thereof, characterized in that solid acid amount of the carrier constituent is equal to or more than 0.20 mmol / g.