OBJECTIVE: To screen and analyze items of the second-generation sub-health questionnaire through various item analysis methods, so as to provide basic data for the further study of sub-health measuring scale. METHODS: The investigation and analysis was completed in Southem Medical University between November 2006 and May 2008. A total of 6 000 college students were selected as the investigation targets with cluster sampling method from a medical university in Guangzhou. 6 000 questionnaires were assigned to them in which the answerer was asked about their somatic symptoms, psychological symptoms and social symptoms, with 5 599 valid ones obtained. Eighty three items were analyzed through five methods based on dispersion, correlation coefficient, factor analysis, t-test and Cronbach's g. RESULTS: At last, 63 items were selected to constitute the item pool of the sub-health scale, which were nominated over 4 times according to the nomination summary of the 5 methods.CONCLUSION: All the 63 items kept in the second-generation sub-health questionnaire feature satisfactory sensibility, representation, independence, significance and intemal consistency, which can accordingly lay a good foundation for the further study of the sub-health measuring scale.