Abstract: In order to reduce the unsafe behaviors of construction workers in high altitude areas and prevent the occurrence of safety accidents, the influence mechanism of cognitive dissonance on unsafe behaviors was explored. A hypothesis model of cognitive dissonance and unsafe behaviors was constructed. A questionnaire survey was conducted on construction workers in high altitude areas. On the basis of reliability, validity and correlation analysis, a regression equation was constructed for hypothesis testing, and the mediation and moderation effects were tested. Finally, the dynamic change process was studied by system dynamics method. The results show that cognitive dissonance has a significant positive impact on unsafe behaviors; occupational burnout plays a partial mediating role in the process of cognitive dissonance affecting unsafe behaviors; social support regulates the first half of the mediation process, and the mediation effect of social support scores with higher scores is more significant; the simulation results show that under the influence of social support and occupational burnout, with the increase of cognitive dissonance level, the occupational burnout level first increases and then decreases, and the level of unsafe behaviors gradually increases.