Abstract: The present paper reports the result of a revisional study of species of the genus Sclerodermus Latreille 1809 (Hymenoptera: Bethylidae) in China. Some Chinese species in the genus are important natural enemies parasitizing wood borers and have been used broadly to control the pests. There are four valid species in China fauna right now: Sclerodermus guani Xiao et Wu 1983, S. sichuanensis Xiao 1995, S. hainanica Xiao 1995, S. pupariae Yang et Yao 2012. A key to distinguish them is provided, including S. harmandi (Buysson 1903) which is suspected to distribute in China. It is considered that S. guani Xiao et Wu 1983 is a valid species rather than S. harmandi (Buysson 1903). For distinguishing the two species, S. guani is re-described in details, including apterous and alate females, as well as alate male with colorous photos, based on its holotype and paratypes conserved in the Insect Collection of Chinese Academy of Forestry. Meanwhile, the re-description of S. harmandi made by Terayama (2006) is cited. A table of diagnostic characters to separate the two species is provided. In the last, the description of S. pupariae Yang et Yao 2012 is given too, including notes on its biology and behavior. It was found that S. pupariae is an excellent biocontrol agent for using in control of wood borer pests, e.g. Massicus raddei, Anoplophora glabripennis, Apriona swainsoni，Xylotrechus grayii (Coleoptera: Cerambycidae), Agrilus planipennis and A. mali (Coleoptera: Buprestidae).