This study aimed to assess the effectiveness of the self-learning module in the development of reading comprehension of grade 4 Amethyst pupils at Caesar Lanuza Elementary School in Brgy. Biñan, Pagsanjan, Laguna. It involved twenty-eight (28) respondents representing the 4th grade from whom the data  was collected and answered two research questions raised, namely: the mean level of reading comprehension of pupils before and after the utilization of self-learning module and the significant difference between the comprehension level before and after using the self-learning module in terms of frustration, instruction, and independence. Two (2) sets of a questionnaire and a self-learning module was issued to gather solutions to the foregoing problem areas investigated it was given before and after reading the validated self-learning module using the pre-test and post-test. The significance of the pre-test and post-test scores of the pupils. The mean score of the pupils pre-test was 5.0714 at 1.4067 standard deviation and a variance of 5.3280 while their post-test mean score was 8.1429 at 1.4067 standard deviation and a variance of 1.9788. When two sets of scores was compared and analyzed using paired t-test employing the Microsoft Excel Data Analysis at 5% level of significance and a degree of freedom equal to 27, the computed t-value of 8.13162 was higher than the critical value of 2.05183. Thus, it can be concluded that the level of the reading comprehension of pupils after the utilization of self-learning module was improved. These findings suggest that the self-learning module positively impacted the performance of grade 4 Amethyst pupils. The increase in the mean score indicated the progress and that the module was effective. The significance of the pre-test and post-test scores of the pupils in terms of Frustration. The mean score of the pupils pre-test was 3.3125 at 0.9465 standard deviation and a variance of 0.8958 while their post-test mean score was 7.5625 at 1.3150 standard deviation and a variance of 1.7292. When two sets of scores was compared and analyzed using paired t-test employing the Microsoft Excel Data Analysis at 5% level of significance and a degree of freedom equal to 27, the computed t-value of 12.6711 was higher than the critical value of 2.1315. Thus, it can be concluded that the level of the reading comprehension of pupils before and after the utilization of self-learning module was significantly different. Based on the study Effectiveness of Self-Learning Modules on Students Learning in English of Lumapenet (2022), there is an improvement on the results of the post-test scores of the pupils in comparison with the scores of their pretest. Therefore, the modular approach in teaching has a significant impact in improving the reading performance of the pupils. The significance of the pre-test and post-test scores of the pupils in terms of Instructional. The mean score of the pupils pre-test was 6.4000 at 0.5477 standard deviation and a variance of 0.3000 while their post-test mean score was 8.2000 at 1.6432 standard deviation and a variance of 2.7000. When two sets of scores was compared and analyzed using paired t-test employing the Microsoft Excel Data Analysis at 5% level of significance and a degree of freedom equal to 27, the computed t-value of 1.96396 was lower than the critical value of 2.776445. Thus, it can be concluded that the level of the reading comprehension of pupils before and after the utilization of self-learning module was insignificantly different. The significance of the pre-test and post-test scores of the pupils in terms of Instructional. The mean score of the pupils pre-test was 8.2857 at 0.4880 standard deviation and a variance of 0.2381 while their post-test mean score was 9.0000 at 0.8165 standard deviation and a variance of 0.6667. When two sets of scores was compared and analyzed using paired t-test employing the Microsoft Excel Data Analysis at 5% level of significance and a degree of freedom equal to 27, the computed t-value of 1.96396 was lower than the critical value of 2.776445. Thus, it can be concluded that the level of the reading comprehension of pupils before and after the utilization of self-learning module was insignificantly different.