Batch experiments were employed to investigate the effect of flocculant and lysozyme treatment on the sludge dewaterability，settling performance and floc characteristics. The results showed that the sludge settling performance was improved in the presence of flocculant and lysozyme alone. When the flocculant and lysozyme worked together, both the sludge settling performance and dewatered speed were further enhanced. The optimum flocculant and lysozyme dosage in the combined system was 2 mL and 0.15 g/g，respectively. And the moisture content of the sludge cake and specific resistance were determined to be 65.7% and 0.08×1012 m, respectively, which were decreased by 25.3% and 75.8% compared with the original mud. The results of extracellular polymeric substance (EPS) and floc shape suggested that lysozyme could change the EPS distribution and crack the floc structure. The absorption and bridge effect of the flocculant improved the sludge dewatering speed. The combination of flocculants and lysozyme increased the number of the two-dimensional fractal dimension of floc, made the floc structure closer and tighter, and improved the moisture ratio that could be dewatered in the sludge. This resulted in the enhanced sludge dewatering performance. This study demonstrated that the combination of flocculant and lysozyme on sludge dewaterbility treatment has a promising application potential.