The purpose of this study was to explore structural relationships of home, teacher and student factors with primary school students’ out-of-school literacy. Specifically, we examined the mediating effects of student attitudes toward literacy between home or teacher factors and out-of-school literacy. The subjects of the study were 2,406 students sampled from 13 elementary schools located in G and I province. We hypothesized a structural model in that perceived family members’ literacy activities, their conversation about students’ literacy activities, and teacher’s instruction such as teacher’s positive feedbacks about students’ reading or writing influence students’ attitudes toward literacy and in turn, students’ attitudes toward literacy influence their out-of-school literacy. The results showed that the home and students’ factors had statistically significant positive effects on school happiness in either direct or indirect ways, while the teacher factor had only significant indirect effects on students’ out-of-school literacy in terms of students’ attitudes. Also, the mediating effects of students’ attitudes toward literacy were relatively stronger than the direct effects between home or teacher factors and students’ out-of-school literacy. Finally, the results revealed that the home, teacher and student factors can contribute to students’ out-of-school literacy regardless of students’ grade, or gender. Finally, it was discussed that future work is needed for comprehensive understanding or improvement of students’ out-of-school literacy.