We have studied the effects of having a reading difficulty on eye movement behaviors such as average duration and number of fixations in three different reading conditions: AP, where participants read paper textbooks aloud; AD, where they read digital textbooks aloud; and SD, where they read digital textbooks silently and follow where the synthesized voice is reading with their eyes. The subjects of this study were 19 skilled readers and six poor readers in the third to sixth grade of primary school. The participants were asked to read textbooks on moral education and Japanese published by Mitsumura Tosho Publishing Co., Ltd. in paper and digital forms, in the above three conditions. Eye movement information was sampled by Tobii Glass 3 with the sampling rate of 120Hz. We were able to map 489 textbook pages and analyzed the eye movements of these pages. Participants were categorized into two groups: a middle-year group with third and fourth grade students, and an older-year group with fifth and sixth grade students. The smaller the difference in duration, the more similar the eye movement of poor readers is to that of skilled readers. In both groups, poor readers showed significantly longer average duration of fixation (p<.05) under the AP condition. In other words, poor readers showed a longer duration of fixation on text than skilled readers did when reading paper textbooks. No significant difference was recorded for the average duration of fixation between conditions AD and SD. For this study, we used real textbooks and allowed participants to read in conditions similar to their normal reading styles, so we cannot investigate more precisely than the above at this time. The results provide an indication that digital textbooks may have positive effects on poor readers’ reading.