Because of the complicated interaction of the sludge compost components, it makes the quality evaluation system of sludge compost appear the fuzziness. According to the physical circumstances of sludge compost, a compost quality evaluation modeling method based on fuzzy neural network is presented. We select the index of sludge compost quality and take the high temperature duration, degrdn rate, nitrogen content, average oxygen concentration and maturity degree as the evaluation parameters. We construct the structure of fuzzy neural network that used for the quality evaluation of sludge compost, and adopt the Levenberg-Marquart optimizing algorithm to train fuzzy neural network. With the ability of strong self-learning and function approach of fuzzy neural network, the modeling method can truly evaluate the sludge compost quality by learning the index information of sludge compost quality. The experimental results show that this method is feasible and effective.