The contact filter paper test and artificial soil test were used to determine the effects of acute and chromic toxicities of municipal sludges from the Yangtze River Delta region of China on earthworms in bronze and violet soils. The results indicated that the toxicities of sludges in the contact filter paper test were higher and faster, and the toxic symptoms were very obvious. The ranges of Rsw-LC50 (sludge/water) of all sludges to earthworms in this study ranged from 0.0010 to 0.0242. In all sludges, the toxicity of Shanghai mud pond sludge was the highest and Shanghai dehydrated sludge 5 was the lowest. But most toxic symptoms in the artificial soil test were not obvious and the earthworm mortalities of all treatments were 0. The influential differences among different sludge treatments on the growth rate of earthworm weight were small. The toxicity of sludges treated with soils on earthworms abased enormously.