In this study, it is aimed to determine the effect of students‟ reading levels on their success rates in mathematics class and on their mathematical problem solving skills. 74 students from two different secondary schools were separated into levelled reading groups after determining the number of books they have read so far and then their academic success rates in mathematics and their mathematical problem solving skills were determined. A problem solving success test consisting of 20 questions prepared with the help of a specialist, a form to determine the number of books read so far, and students‟ mathematics class written exam scores were used as data gathering tools. A quantitative analysis was used in analysing the correlations of gathered data. Data analysing was made by mean of one-way independent sample variant analysis (one way ANOVA). At the end of the study, it was found out that extensive reading had no meaningful impact on students‟ mathematic success rates and on their problem solving skills and steps.