共同基金作为我国资本市场规模最大的机构投资者，近年来抱团投资现象愈发明显，其投资趋同行为是“同甘”还是“共苦”？本文选取了我国普通股票型和偏股混合型共537只基金2016年-2021年的数据作为研究样本，借鉴智君研究构建了基金的季度抱团率指标，并应用单因子、三因子和四因子定价模型衡量基金业绩，研究基金抱团比率对基金绩效的影响。研究发现：（1）“抱团同甘”，基金抱团比率越高，未来一期基金业绩越好，但抱团对业绩的提升效果是不可持续的，从长期来看，抱团率越高基金业绩表现越差；（2）从市场环境看，“抱团同甘”的投资策略只有在市场为牛市的环境下才有效，熊市环境下与其他基金抱团不能显著改善基金业绩；（3）从历史业绩看，只有历史业绩较差的基金才能通过与其他基金的抱团提升业绩，而业绩表现良好的基金抱团并不能实现业绩的改善；（4）抱团对基金业绩的影响是通过驱动抱团股股票的市场股价估值水平来提升未来业绩的。文章对基金抱团行为的相关研究进行了拓展和丰富，对我国基金经理的投资策略选择和市场投资者的选择具有一定的借鉴意义。

The phenomenon of mutual funds’ group investment has become more and more obvious in recent years, as the important institutional investors in China's capital market, is their investment convergence behavior "sharing weal" or "sharing woe"? This paper construct the evaluation index of fund group behavior based on ZhiJun research, and applies Camp’s single factor, Fama-French three factor and Carhart's four-factor risk pricing model to extract excess return, and study the impact of fund clustering on fund performance using the samples of common stock funds and biased stock hybrid funds in China during 2016-2021. It’s found that, "group can share weal", fund managers’ group behavior can significantly improve their performance, but the degree of improvement is limited. In the long run, the higher the group rate, the worse the fund performance; From the market situation, only in the bull market, the group behavior can improve the fund performance, in the environment of bear market, group behavior can’t increase the fund return; From the perspective of historical performance, only funds with poor historical performance can improve their performance by pooling with other funds, while funds with good performance can’t improve their performance; The influence of group on fund performance is by driving the stock price bubble of group stocks. This paper has enriched the research on fund group behavior and has certain reference significance for the investment strategy selection of fund managers and market investors in China.