The present study was undertaken to examine the causal relationship between family factors and reading literacy among Iranian fourth graders mediated by valuing reading and reading habits of students based on PIRLS 2011 data. To this end, 5758 students (girls and boys) and their parents were sampled. The data from international PIRLS 2011 test as well as two contextual questionnaires (Student Questionnaire and Home Questionnaire) were used and analyzed using SPSS and Amos software. The overall fit of the proposed model was confirmed. Moreover, the proposed model for girls and boys had a desirable goodness of fit into the data. Among the paths, the effects of SES on reading habits of students, SES on reading literacy of students, and reading habits of students on their reading literacy were positive and significant. The chi-square results for girls and boys showed that there was no statistically significant difference between them.