Abstract: Based on empirical research of the data of NO.6 Nationwide Surveys in Chinese Private Enterprises,this paper analyzes the private enterprise's characteristics on union's acknowledgement The research indicates that,entrepreneur's personal characteristic is better, the private enterprises has a tendency toward stronger acknowledgement of trade union,the private enterprises need more crowded labor force,their business management is better,their size is larger,they are more in favor of trade union.On the contrary,the private enterprises in developed area are less in favor of the trade union than the ones in developing area.We need to widen the way of trade union's acknowledgement and pay more attention to the private enterprises in low acknowledgement industries and regions.