Thirteen sludge samples from Guangzhou, Shanghai and Dalian were collected and analysed for heavy metals to investigate the distribution and variation trend of heavy metals in sludge from wastewater treatment plants in Chinese coastal areas. The results showed that contents of heavy metals in sludge varied significantly, and the average contents exhibited an order of Cr > Zn > Cu > Pb > As > Hg > Cd. Additionally, contents of Cr, Cu and As exceeded their corresponding standard levels. Compared with contents of heavy metals in 2006 and 2001, content of Zn in sludge increased while contents of Cr, Cu and As decreased. Results also indicated that the industrial sludge was more seriously polluted than domestic sludge in terms of Zn, Cu and As. Only 23% sludge samples exceeded the standards for fertilization of sludge, suggesting that most of the sludge could be disposed by land application. These results also provide further information about the establishment of ocean disposal assessment for sludge.