中文摘要：

通过研究风险投资减持过程中的盈余管理，本文发现，在减持过程中，风险投资试图影响管理层，以提高减持前的会计收益，从而获得更高的减持收益，但这种模式只存在利用后半年定期报告进行减持时机选择的情况下，这意味着风险投资的盈余管理减持时机选择有赖于上市公司本身的盈余管理动机。且随着风险投资在减持前持股比例的增加，风险投资减持对后半年季度盈余管理的影响能力进一步增加。进一步研究发现，由于国有风险投资对被投资企业的谈判能力更强，参与程度更高，其表现出比非国有风险投资更显著的减持机会主义。在控制内生性问题后，上述结论依然没有发生重大变化。

英文摘要：

As sponsors of IPO firms, Venture Capitalists（VCs） play very important role in capital market. According to the investigation of Zero2Ipo research institute, about 50% IPO firms in Small Board and GEM witness the participation of VC. In order to improve in vestor protection, the government in China mandatorily stipulated equity lockup period of VC after IPO. The equity selling after lockup period will not only bring great pressure to the market, but also have a negative impact on IPO firms, for monitor and value-adding service will disappear as VC exit. So VCs＇ behavior after the expiration of lock-up period has a sig nificant influence on the healthy development of capital market. VCs are different from other large shareholders of IPO firms in several aspects. For ex- ample, the limited lifetime and special organizational structure of VCs mean that VCs must pay attention to how to get back their original investment and receive high returns, so VCs are likely to participate in portfolio firms＇ IPO activities opportunistically and have moral haz ard problems. However in contrast, VCs＇ investment is a repeated game, so the reputation of professional investors is crucial to their future investments and financing. In this case, the reputation cost and litigation cost must be considered when selling equity after Iockup period. Therefore they carefully make selling decisions, and even tried to hold overvalued IPO shares in order to build a reputation. So when selling equity, VCs will behavior opportunistically or professionally, depending on their consideration of the benefit and cost. Currently, VCs＇ equity selling after the expira- tion of lock-up period in China is still a new phenomenon, with few studies discussing it. And China＇s capital market is an emerging market without a long history. Although the regulatory systems are being improved, there are still some problems with the market mechanism and support systems, which result in low investor protection and further exacerbate the moral hazard pro