Abstract: Objective: To analyze the incidence trend of pulmonary tuberculosis (PTB) in Haining City, Zhejiang Province from 2005 to 2024, and to explore the effects of age, period, and birth cohort on the risk of PTB, so as to provide evidence for optimizing prevention and control strategies. Methods: Data on reported PTB cases in Haining City from 2005 to 2024 were collected. The Joinpoint regression model was used to calculate the annual percent change (APC) and average annual percent change (AAPC) to analyze incidence trends. An age-period-cohort model was established to evaluate the effects of age, period, and cohort. Results: A total of 7 774 PTB cases were reported in Haining City from 2005 to 2024, with an average annual reported crude incidence rate of 45.71 per 100 000. The crude incidence rate in males (61.65 per 100 000) was significantly higher than that in females (29.28 per 100 000, χ²=974.45, P<0.001). The total population agestandardized incidence rate showed a declining trend (AAPC=-7.70%, P<0.001), with a rapid decline from 2005 to 2013 (APC=-11.51%, P<0.001), followed by a plateau phase from 2013 to 2019 (APC=-0.05%, P>0.05). The age-period-cohort model showed that, the longitudinal age curve indicated the highest crude incidence rate in the 20–24 years age group, while the cross-sectional age curve exhibited a bimodal pattern, with peaks observed in the young adult group (25–29 years) and the elderly group (75–79 years). using the 2010–2014 period as a reference, the risk of PTB decreased over time, declining from 1.79(95% CI: 1.56–2.04) in 2005–2009 to 0.54 (95% CI: 0.45-0.66) in 2020–2024. Using the 1970 birth cohort as a reference, the risk of PTB decreased with later birth cohorts. Conclusion: The age-standardized incidence of PTB in Haining City showed a significant downward trend from 2005 to 2024, The risk of PTB is jointly influenced by age, period, and cohort factors. Future prevention and control efforts should focus on the elderly and male populations, and strengthen interventions for individuals with latent tuberculosis infection.