This study was conducted with the aim of testing the causal relation among task value, cognitive engagement, achievement emotions, academic self-regulation, and mathematics achievement. For this, 560 students (267 boys and 293 girls) were chosen from the high school 3rd graders who studied mathematics in high schools of Tehran by multistage clustering sampling and answered the task value subscale questionnaire (Pintrich and DeGroot, 1991), Cognitive Involvement Scale (revised (2F-R-LPQ)) (KamberBigs and Liong, 2004), Pre-exam Development Scale (AEQ) (Pekran, Quitz, Teets and Perry, 2005) and achievement Self- regulation Scale (Pintrich and DeGroot, 1990). The results of structural equation analysis with use of experimental data showed that academic achievement is influenced directly and indirectly by predictor variables such as task value, cognitive engagement, academic achievement emotions and academic self- regulation. The results of this study show that all the indices except for AGFI were reported highly satisfying and the model fits the data well and this points to the linear relation between latent variables and structures. Consequently, the general hypothesis of the study which is “the preconceived pattern of causal relation between task value and academic achievement with the mediation of cognitive engagement, academic achievement emotions and academic self-regulation fits the data patterns” was confirmed.