Mangrove wetlands, due to their attributes, could receive a large amount of pollutants (e.g. heavy metals) from local drainages, rivers and tides. Heavy metal pollution in mangrove wetlands has aroused great concern and a great number of relevant researches have been conducted in last three decades. The paper here reviews the research progress and some issues relating to distribution and transfer of heavy metals in mangrove wetlands, response and tolerant mechanisms to heavy metals by mangrove plants. In addition, it also summarizes metal purifying effects by mangrove system. Finally, the paper discusses the trends of future researches on mangrove wetlands.