The main purpose of this research was to investigate the relationship between needed skills for evaluation and academic achievement of virtual students based on constructivist approach. The methodology of research was correlational. The instrument was a researcher-made questionnaire about needed skills for evaluation (a=0.92) and f academic achievement test for two ago semester. The population consisted of all virtual universities’ students (2009-2010) in Iran. The sample group was selected randomly based on Krejcie-Morgan's sample size table (363 students). Pearson Correlation and structural equation model was used for data analysis. Findings indicate that virtual students’ academic achievement influenced by the principles of writing, participating in the process of teaching -learning in the network, electronic portfolio, and time management. The direct effect of synchronous interaction with classmate (0.473), priority of important and emergency affairs (0.395), process portfolio (0.290), principles of scientific writing (0.29), process-producer portfolio (0.250), technical principles (0.25). Based on structural equation test, Chi-Square=117.682, GFI= 0.951, AGFI=0.921, P-Value= 0.000, RMSEA=0.055. Thus, the tested model was acceptable.