Background: Sub-health status (SHS), a third state between good health and disease, can easily develop into chronic diseases. It is found to be influenced by lifestyle behaviors and health consciousness. Method: A cross-sectional survey using a four-stage stratified sampling method was conducted from March to September 2018 among Chinese urban residents. Questionnaire included demographic characteristics, lifestyle behaviors, health consciousness, and Sub-Health Measurement Scale V1·0. A total of 3535 qualified adults were included in the analysis. A structural equation model (SEM) was adopted to analyze relationships among lifestyle behaviors, health consciousness, and SHS. A bootstrapping method was applied to estimate the mediation effect of health consciousness. Findings: Lifestyle behaviors had a strong direct association with physical sub-health (β=-0·207), faint direct association with social health (β=-0·075), and no significant direct association with mental sub-health (β=-0·050). Health consciousness had a strong direct association with physical sub-health (β=0·480), mental sub-health (β=0·601), and social sub-health (β=0·559). Health consciousness had a complete mediation effect in the relationship between lifestyle behaviors and mental sub-health, and a partial mediation effect in the relationships between lifestyle behaviors and physical and social sub-health. Interpretation: Negative health consciousness and unhealthy lifestyle behaviors associated with worse SHS, which gives a clue that improving health consciousness and altering lifestyle behaviors maybe good for changing sub-health status to health status, which needed proven of further researches. Funding Statement: This research was supported by the National Natural Science Fund, National Natural Science Foundation of China (No: 71673126), and the Science and Technology Planning Project of Guangzhou City of China (No: 201803010089). Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: Verbal informed consent was obtained from every participant prior to data collection. Verbal consent was deemed sufficient by the Nanfang hospital ethics committee because participants had previously volunteered for the study and could refuse to participate. All data were kept strictly confidential.