The purpose of the current study was to investigate both student-level and school-level factors influencing reading literacy of students in Turkey by using PISA 2018 data. The study focused on reading literacy since the main subject of PISA 2018 was selected as reading literacy. The design of the study is a correlational research examining the relationship between student and school variables and reading literacy. The stratified random sample consisted of 6890 15-year students from 186 different schools. Data coming from PISA 2018 dataset were analysed by Hierarchical Linear Modelling (HLM) at student and school levels. Student-level variables of disciplinary climate in test language lessons, enjoyment of reading, information and community technologies (ICT) competence, parental emotional support, perceived discriminating climate, and perceived cooperation significantly predicted reading literacy, while reading literacy was also predicted by school-level variables of proportion of parents involved in the school, shortage of educational material, student behaviour hindering learning, and teacher behaviour hindering learning. Fifty-seven percent of variance between reading literacy scores of the students were caused by differences between schools. Student-level variables which are disciplinary climate in test language lessons, enjoyment of reading, ICT competence, parental emotional support, perceived discriminating climate, and perceived cooperation significantly predicted reading literacy. On the other hand, school-level variables predicting reading literacy significantly were proportion of parents involved in the school, shortage of educational material, student behaviour hindering learning, and teacher behaviour hindering learning. By considering results of the current study, collaboration between school stakeholders is recommended to increase performance of the students.