PURPOSE: The Tianjin Health and Chronic Disease Study (THCDS) is a longitudinal dynamic cohort study established in 2022, aiming to investigate risk factors and intervention targets of common non-communicable diseases (NCDs) in Tianjin, China. PARTICIPANTS: A total of 14 324 participants (average age: 53.48, 34.8% females) were recruited for the baseline survey from July 2022 to November 2023. All participants underwent routine medical examination, including anthropometric (height, weight and blood pressure), ECG, colour Doppler ultrasound (thyroid, carotid artery, heart, abdominal and reproductive system), chest imaging measurements (X-ray or computerised tomographic scanning), and plasma, urine and faeces sample test and a standardised questionnaire, including demographic information, lifestyle factors (smoking, alcohol consumption, diet, sleep factors, physical activity, cognitive activity and social activity) and self-reported history of common chronic diseases. Participants older than 60 were also invited to perform cognitive function tests using the Montreal Cognitive Assessment scale. Follow-ups were tracked annually through routine medical examinations and standardised questionnaires to detect their health status. FINDINGS TO DATE: Key baseline findings revealed sex disparities in disease prevalence and clinical characteristics, with males showing higher rates of hypertension (46.60% vs 34.23%), type 2 diabetes (17.39% vs 9.54%) and gout (33.47% vs 15.59%), while females had higher prevalence of hyperlipidaemia (15.47% vs 18.26%), insomnia (5.42% vs 10.00%) and cancer (1.75% vs 3.23%) (all p<0.05). Females demonstrated higher cognitive scores but lower scores in naming/abstraction compared with males. Furthermore, based on the baseline data, we also found that the combined elevation of fasting glucose and serum uric acid levels significantly correlates with non-alcoholic fatty liver disease, especially in individuals without self-reported diabetes status. FUTURE PLANS: THCDS is an ongoing prospective cohort with long-term follow-up (at least 15 years). Ongoing follow-ups will be used to investigate longitudinal trajectories of risk factors and chronic diseases and to identify modifiable determinants to inform NCD prevention strategies. TRIAL REGISTRATION NUMBER: ChiCTR2400083075; pre-result.