The aim of this study was to examine the moderator role of gender and socioeconomic status (SES) factors in the relationship between students' metacognitive skills and reading performance. The sample of the study was 6890 students in the age group of 15 years-old who participated in the Programme for International Student Assessment (PISA) in 2018 from Turkey. 3396 of the participants (49.30%) were female and 3494 (50.70%) of them were male. Of the participants, 2273 (32.99%) were classified as low, 2273 (32.99%) as medium and 2344 (34.02%) as high socioeconomic level. Moderator effects were tested with the multi-group structural equation modelling approach. Results revealed that SES and gender moderated the relationship between metacognitive skills and reading when controlling for other variables. Female students scored lower than male students in low and medium SES group, however they scored higher in the high SES group even after controlling for metacognitive skills, liking reading, and self-concept of perception of competence and difficulty. This means gender differences in reading scores were largely driven by SES. Therefore, the effect of these two factors should be taken into consideration while working on metacognition and reading. Moreover, it was advised to integrate training of metacognitive strategies in school curriculum and encourage reading engagement in order to reduce the effect of those factors.