Background: Older adults are at a higher risk from COVID-19. Individual preventive behaviors including frequent hand washing, mask wearing, and social distancing play important roles in reducing the transmission of COVID-19 in the community. This study aimed to identify the determinants of three preventive behaviors of older adults during the COVID-19 pandemic by using an Integrated Social Cognition Model.Methods: Using a prospective study design, 516 Chinese older adults from Hubei province of China (mean age = 67.55 years, SD = 6.60, 57.9% females) completed two online questionnaire surveys. The demographics, social cognition constructs (motivational self-efficacy, risk perception, attitude, subjective norm, health knowledge, intention, volitional self-efficacy, planning, action control) and three preventive behaviors were measured during the first-wave online survey from 18 May 2020 to 7 June 2020. One month later, three preventive behaviors were measured again during the second-wave online survey. Data were analyzed by structural equation modelling.Results: Models showed attitude, motivational self-efficacy and subjective norm were consistent predictors of intention, motivational self-efficacy was a consistent predictor of volitional self-efficacy, planning and volitional self-efficacy were consistent predictors of action control, and health knowledge was a consistent predictor of behaviors across all three preventive behaviors. In addition, mediating relationships were found in the model of hand washing behavior. In particular, planning (β = .109,p= .042) and action control (β = .056,p= .047) mediated between volitional self-efficacy and hand washing respectively. Action control also mediated between planning and hand washing (β = .087,p= .044). Moreover, the inclusion of past behaviors in three models attenuated most of the structural relations.Conclusions: The current study’s findings basically supported the Integrated Social Cognition Model and identified key modifiable determinants of preventive behaviors. Based on this model, future interventions aiming to promote COVID-19 preventive behaviors among older adults are warranted.