The general aim of the present research was to study the impact of active methods of teaching on reading literacy development of Mazandaran fourth and fifth grade elementary school students. Regarding the purpose, this research was applied, and given the non-equivalent group and pretest – posttest plan in the experimental and control groups for each grade, it could be viewed as a quasi-experimental research. The statistical population of this study included 40438 fourth and 40263 fifth elementary school students. Among the population mentioned, 384 fourth graders and 384 fifth graders from 40 classes have been selected as the control and experimental groups based on the multi-stage random-cluster sampling method. The data collection instruments include reading literacy tests containing literary and informational texts, the validity of which was confirmed by the educational experts. The reliability of the texts, was 0.92 and 0.88 for the literary texts and the informational texts, respectively. The results showed that active methods of teaching are effective in reading literacy development of both literary and informational texts for fourth as well as fifth graders. The results also showed that there is no significant difference between the students of the two grades according to the reading literacy development of the literary and informational texts.