Abstract: In 2022，the 20th National Congress of the Communist Party of China emphasized the importance of reinforcing employment priority policies，underscoring its pivotal role in the subsequent phases of Chinas economic and social development This paper introduces labor market frictions and firms entryexit mechanism into a DSGE model，examining the impact of the epidemic on Chinas macroeconomic fluctuations through four different forms of labor market shocks The results indicate that：Firstly，shocks on the labor supply or demand sides could result in a significant decrease in overall output，consumption，and the number of enterprises The size of individual enterprises contracts during the shock on supply side and expands during the shock on demand side Secondly，the simulation results indicate that even the shock last only one quarter，macroeconomic fluctuations could persist for several years，raising concerns about the speed of macroeconomic recovery after shortterm shocks Thirdly，the public health emergency shock could initially lead to an increase in unemployment，then transmit to the enterprise side，causing the exit of small and mediumsized enterprises This in turn，further suppresses labor demand，forming a positive feedback loop Under the mutual reinforcement of the two mechanisms，the shortterm shock could bring about sustained effect Finally，this paper conducts policy simulations on the baseline model，analyzing the mitigating effects of relief policies such as social security benefits and credit support during the shock
The potential contributions of this paper are reflected in four aspects：Firstly，this paper studies the relationship between Chinas labor market and the macroeconomic fluctuations in a DSGE framework，which is neglected by the domestic macroeconomic studies due to the longterm stability of the unemployment rate Secondly，through the inclusion of firms entryexit mechanism，this paper delineates the survival challenges faced by small and mediumsized enterprises during public health emergency shock Thirdly，by introducing four different labor market shocks，the paper analyzes the specific channels through which the epidemic affects the labor market and the macroeconomy Lastly，this paper demonstrates that labor market frictions and the bankruptcy of small and mediumsized enterprises could form a positive feedback loop，collectively prolonging the impact of shortterm shocks，providing theoretical basis for policy measures such as stabilizing employment and supporting small and mediumsized enterprises

Key words: labor market friction, endogenous firm entry, shock of public health emergency, recovery speed of macroeconomy

摘要： 本文在一个DSGE模型中引入劳动力市场摩擦及企业的进入退出机制，通过四种不同形式的劳动力市场冲击考察了疫情对中国宏观经济波动的影响。结果表明，疫情冲击将首先导致失业增加，然后传导至企业端，引起单个企业产出下降和中小企业退出，进一步抑制对劳动力的需求，形成正反馈循环。在劳动力市场摩擦和企业数目下降两个机制的互相强化下，短期冲击会带来持续性的影响，仅存在一个季度的冲击也会导致宏观经济的波动持续数年。最后，本文通过政策分析为稳定就业、纾困中小企业等举措的有效性提供了理论依据。

关键词: 劳动力市场摩擦, 企业进入退出, 公共卫生事件冲击, 经济恢复速度