Objective:To analyze the effect of Internet use on health lifestyles of Chinese older adults in urban and rural are-as,so as to provide references for guidance of health lifestyles among older adults.Methods:Using the nationally representative da-ta from the China family panel studies in 2018 and its follow-up in 2020,3812 participants were analyzed in the study.The fixed effects model for panel data was performed to examine the effects of Internet use on health lifestyles.The heterogeneity of urban and rural areas was analyzed and several robustness checks were also conducted in the analysis.Results:The results of the fixed effects model based on panel data suggested that Internet use played an improving role in the lifestyles of urban older adults(β=0.09,P=0.01).The importance evaluation of Internet use had a positive impact on the lifestyles of older adults(β=0.07,P=0.03)as well as urban older adults(β=0.10,P<0.01)from 2018 to 2020.Compared to rural older adults,Internet use had a more significant effect on health lifestyles among urban older adults.Conclusion:The findings show that older adults'Internet use has a significant effect on their health lifestyles and older adults who obtain information from the Internet with higher importance evaluation tend to adopt healthier lifestyles.Therefore,it is recommended to focus on guiding the elderly to obtain information from Internet and pay more at-tention on the Internet use and public health of older adults living in rural areas so that more older adults can share the fruits of in-formatization development.