The purpose of present study was to investigate the mediating roles of self-system processes and academic emotions in the relationship between autonomy supportive environment and academic engagement. The sample consisted of 461 Shiraz University students. The research instruments included academic engagement questionnaire (Reeve, 2013), basic psychological needs scale (Gagne, 2003), autonomy supportive environment questionnaire (Assor et al, 2002 & Assor 2012), hope scale (Pekrun et al, 2002), curiosity questionnaire (Litman et al, 2010), and empathy questionnaire (Vossen et al, 2016). The findings showed that autonomy supportive environment had direct effects on self-system processes and academic engagement and an indirect effect on academic engagement by mediating of self-system processes and academic emotions. Autonomy supportive environment had an indirect effect on academic emotions by mediating of self-system processes. Self-system processes had direct effects on academic emotions and academic engagement, furthermore by mediating of academic emotions had an indirect effect on academic engagement. Academic emotions had a positive and significant effect on academic engagement. Accordingly, self-system processes and academic emotions played mediating roles in relationship between autonomy supportive environment and academic engagement.