How to efficiently dispose of the urban water-supply plant sludge has become an urgent task of controlling pollution caused by municipal solid waste. This paper is an experiment on autoclaved sludge brick, which is mainly made of sludge from the water-supply plants, fly ash, lime, sand and cement, integrated with the manufacturing process of autoclaved fly ash brick. By orthogonal optimal process, we get the optimal parameters for making sludge bricks as follows: W sludge : W ash : W lime = 15%: 45%: 15%, stirring intensity being 1400r/min, forming and curing condition being the constant temperature and humidity Curing Box (60 °C, humidity 95%), and autoclave curing condition being 1.2Mpa (time 10h). With the optimal parameters, the compressive strength of the produced bricks reaches 20.8Mpa, and its flexural strength reaches 5.4 Mpa. Besides, stirring conditions, forming and curing conditions together with the influence of curing conditions on autoclaved sludge bricks’ mechanical properties are discussed.