Wetland ecosystem, the transitional region between terrestrial ecosystem and aquatic ecosystem, plays a crucial role in global carbon and nitrogen cycle, flood constraint, runoff regulation, climate improvement, pollution prevention and organismal habitats supply. However, as a consequence of human beings' reclamation and contamination in the past centuries, wetland ecosystems around the world have been destructed and their total area has being declining. Hence, it is urgent to restore wetland ecosystem resources and its ecological function. Microorganisms are one of the predominant participants associated with the function of wetlands. To accomplish wetland restoration scientifically and efficiently, it is indispensable to reveal the responding mechanism of microbial variation due to wetlands' reclamation and restoration. In this study, a series of lands under different utilized types were selected as sampling sites in Nanjishan Wetland National Nature Reserve of Poyang Lake, which located in Jiangxi Province, China. The sites were 38, 48 and 92 year-old reclaimed lands (named RL38, RL48 and RL92, all were paddy fields), 25-year-old retired cropland (RC25) and native wetland (NW). In May 2011, surface soil samples (0-20 cm depth) were collected using earth boring auger in these sampling sites. Biolog-ECO plates were performed to survey the sole-carbon-source utilization of soil microbial communities. Average well colour development (AWCD) of all 31 carbon sources and the 6 kinds of carbon sources were calculated respectively. Microbial community indices calculation and principal components analysis (PCA) were carried out to analyze the variations of functional diversity of soil microbial community in exponential phase. It aimed to preliminarily reveal: 1) the effects of reclamation on the functional diversity of soil microbial community; 2) whether it was efficient at microbial level for wetland restoration by returning farmland to lake wetland. In consequence, 1) the average well colour development (AWCD) of all the soil samples was at a low level during the initial 48 hours. Subsequently, all the AWCDs presented a rapid rising in addition to the 92-year reclaimed land. 2) Generally, the order of AWCD of soil microorganisms was as follows: RC25 > NW > RL38 > RL48 > RL92. Notably, it was significantly higher in retired cropland and native wetland than in reclaimed lands (P<0.01). 3) The AWCD variation of carbohydrates, carboxylic acids and amino acids among sampling sites accorded with the total AWCD of all the 31 sole-carbon sources. 4) According to the microbial functional Richness index and the comprehensive loading scores of PCA, the utilization ability order in exponential phase among sampling sites was RC25 > NW > RL48 > RL38 > RL92. On the first two axes, a total 53.22% variation of functional diversity was explained. The results indicated that 1) the functional diversity of soil microbial community was significantly lower in reclaimed lands than in native wetland and decreased with the extension of reclamation age; 2) soil microorganisms associated with metabolism of carbohydrates, carboxylic acids and amino acids were most apparently affected by reclamation. 3) it was efficient, to some extent, to recover the soil microbial metabolic activity by returning the farmland to lake wetland.