This study was conducted to assess the reading comprehension among the Grade 4 pupils in an Integrated School in the District of Tangalan. The result of the study was the basis on the development of an instructional reading material. The design-based research was used in this study using IPO model. The participants were the 66 Grade 4 pupils and 10 teacher- experts. Reading comprehension test and learning material evaluation tool were the data gathering instrument. The data were analyzed and interpreted using descriptive and inferential data analysis. The result showed that the reading comprehension in English of Grade 4 pupils is low. Based on the result of the study, an instructional material was developed. The instructional material offered a variety of engaging activities, including word boxes, missing letter challenges, collaborative group activities, reading experiences, interactive games, and visual aids for descriptive analysis. The level of acceptability of the developed instructional material for Grade 4 was very highly acceptable as to content, instructional quality, prints, design and layouts. The level of reading comprehension of Grade 4 pupils before the intervention was low but after using the developed instructional material, it became moderate. Hence, there is a significant difference on the reading comprehension of grade 4 pupils before and after using the instructional material.