Guangdong is one of the provinces with the most mangrove resources in China. There are 31 species, 17 families of mangrove plants and 21 438.3hm² of mangrove wetlands which mainly distribute in western Guangdong and Pear River Delta. Mangrove has important ecological functions of preventing or reducing natural disasters, purifying environment, moderating regional climate, conserving biodiversity and so on. Conservation and development of mangrove is one of the eight major forestry projects in the ecological construction of Guangdong Province. In this paper, the ecological functions of mangrove were analyzed; the mangroves importance for the construction of forestry ecological province and its present situation of conservation and development in Guangdong were discussed, and some threatening factors such as utilization of mangrove wetlands for cultivation or aquiculture, expansion of urban areas in coastal region and wastewater pollution were pointed out. In the end, some suggestions for conservation and development of mangrove were put forward.