Knowledge sharing not only promotes communication among teachers to achieve self-professional growth but also facilitates knowledge innovation. Thus, knowledge sharing among preschool teachers deserves attention. This study explored the factors influencing preschool teachers' knowledge-sharing behaviors. A questionnaire was administered to 297 preschool teachers using a Norm Activation Model from a thinking style perspective. Data analysis was performed using partial least square-structural equation modelling (PLS-SEM). The findings indicate that executive thinking style preschool teachers showed a significant positive influence of awareness of consequences; legislative thinking style preschool teachers showed a significant positive influence of awareness of consequences and ascription of responsibility; awareness of consequences had a significant positive influence on ascription of responsibility; awareness of consequences and ascription of responsibility had a significant positive influence on personal norms; and personal norms had a significant positive influence on knowledge-sharing behavior. Meanwhile, the influence of executive thinking style on ascription of responsibility, legislative thinking style on ascription of responsibility, and awareness of consequences on personal norms emerged as significantly different among preschool teachers in two different contexts: interpersonal sharing and Internet sharing. This study confirmed the factors influencing preschool teachers' knowledge-sharing behaviors from a thinking style perspective and provides suggestions for improving preschool teachers' knowledge-sharing behaviors.