The results of this work have demonstrated that sludge-coal fly ash-soil-cement brick can be successfully produced using water treatment plant sludge and cyclone fly ash under the conditions and manufacturing methods used in this study. The proportion of sludge and fly ash in the mixture soil-cement and soil-lime was the two key factors affecting the quality of brick. The massive brick built with the composition of 60 % soil, 12 % cement, 8 % coal fly ash and 20 % water treatment plant sludge showed satisfactory results regarding to the mechanical and physical requirements (resistance to compression and absorption of water) stipulated by the Brazilian standards. This study showed that water treatment plant sludge and coal fly ash could be used as brick material for economic and environmental sustainability. The incorporation of these wastes into brick production is a suitable alternative to their current disposal paths.