In this study, four computer-based reading texts with text related static and animated visuals and background sounds were created with a visual programming language by the researchers for fourth grade students. These texts included before-reading, during-reading and after-reading activities. The purpose was to see the effect of these computer-based reading texts on students' reading comprehension. In an experimental research design, elementary school fourth grade students (n = 60) were randomly assigned to either computer-based reading (n = 31) or traditional reading (n = 29) environment. The groups completed a pretest, before-reading, during-reading and after-reading activities and then a posttest. The research has been completed in a six-week period: the pretest in the first week, the four texts in the following four weeks, and the posttest in the sixth week respectively. The results indicated that the computer-based group had significantly better posttest scores than the traditional group had and had significantly better improvement from pretest to posttest. However, there was no significant difference between students' reading comprehension results from pretest to posttest in the traditional group. As a result, presenting students with multimedia-supported reading activities had a positive effect on their reading comprehension. Thus, we recommend teachers to use visually-supported computer-based reading texts to improve students' reading comprehension.