A process for treatment of municipal wastewater plant sludge to the criteria of Class A biosolids. The process uses hydrogen peroxide and thermo-oxidation to reduce volatile suspended solids to meet the criteria. On a batch basis, waste activated sludge is introduced into a reactor; the concentration of the waste activated sludge is adjusted to about 1.5% total suspended solids with secondary effluent, if necessary; the reactor is mixed; the reactor is pre-heated to an operating temperature in a range of about 65° C. to about 90° C.; subsequently, a 50% solution of laboratory grade hydrogen peroxide is introduced into the bottom of the reactor; and the contents are heated for at least 4 hours.