Academic engagement explains the extent to which learners identify with and value academic conclusions, and take part in academic and non-academic activities. The present study explores, quantitatively, a causal model of both psycho-social and motivational factors in academic engagement and their potential impacts on academic achievement outcome. The sample of this research consisted of 480 undergraduate students at Alzahra University, Tehran, Iran who were selected by stratified random sampling method. The instruments which used in this study were The Academic Success Inventory, Boekaerts" Motivation control scale (1987), Kuhl's Action Control scale (ACS-90) (1994), Pintrich et al.'s Motivated Strategies for Learning Questionnaire (MSLQ) (1991), Schraw & Dennison's Metacognitive awareness inventory (MAI) (1994), Boekaerts' Intended/actual goals scale (1987), Zimbardo & Boyd's future time perception inventory (ZPTI) (1999), & Schaufeli, et al"s Academic Engagement scale (2002). Structural equation modeling (SEM) through AMOS-22 was used for data analysis. The results indicated that motivational control-emotional states & competencies, self-efficacy, metacognition, action control-initiative persistence & disengage persistence-had significant effects on academic engagement. Also academic engagement can affect academic performance mediating