A method for preparing flower ceramic particles with urban water supply sludge belongs to the field of environmental technology, and relates to the resource utilization of solid waste. Materials accounted by dry weight rate, including 30-50 percent of water supply sludge, 10-30 percent of coal slurry, 20-30 percent of flint clay, 5-7 percent of Chinese chestnut shell, 8-10 percent of waste glass and the like, are dried, grinded, mixed and uniformly agitated to be prepared into spheres 6-15 mm in particle diameter. The spheres are subjected to pre-heating torrefaction and cooling so as to form the high performance flower ceramic particles. The ceramic particles prepared by the method are light and have loose and porous surfaces, can absorb a considerable amount of water, and has proper ability to keep nutritious substances. Compared with soilless substrates such as sand and wood chips, the flow ceramic particles have the characteristics of cleanness, neatness, attractiveness in shape, lightness, no pollution, cleanable performance, durability, higher stability in chemical property and the like.