In order to promote the standardized and orderly development of network freight industry, the characteristics of network freight mode was summarized by the method of sampling survey. The key factors that affect the service ability of network freight enterprises were concluded through the combination of field research and benchmarking analysis. The service capability evaluation index system of network freight enterprises was established in aspects of security management, service quality, operation efficiency, information technology and business scale, etc. Meanwhile, fuzzy analytic hierarchy process (AHP) was improved to clarify the index weights of seven key factors affecting the service capability of network freight enterprises, and an empirical analysis was carried out with a certain enterprise as a case. The result shows that three key factors affecting the improvement of service ability of network freight enterprises are information security management system, normal freight ratio and cargo loss ratio, and their weights are 0.133, 0.093 and 0.093 respectively. The evaluation result obtained by index system is consistent with the enterprise′s actual situation. Meanwhile, seven indicators including safety, standardization, technology, etc. cover all aspects of network freight enterprise transaction, transportation and settlement, which can comprehensively reflect the service capability of network freight enterprises.