The frequently-used sludge treatment technologies at home and abrad were intrduced in this paper. The application of new wet oxidation process in sludge treatment and the transformation mechanism of organic matter was discussed. Based on relevant research results, the development history from the wet air oxidation (WAO), the catalytic wet air oxidation (CWAO) to catalytic wet peroxide oxidation (CWPO) are analyzed. It is pointed out that new catalysts and efficient oxidants are the future development direction of sludge wet oxidation technology.