Previous studies revealed that young children learn novel word meanings by simply reading and listening to a printed book. In today's classroom, many children's e-books provide audio narration support so young readers can simply listen to the e-books. The focus of the present study is to examine the effect of e-book reading with audio narration support on the novel vocabulary learning of first grade students with advanced, average, and poor reading abilities. The effect of adding teacher's word explanation on novel word learning was also examined. By employing a within-subject design, students read an e-book that contained ten explained words and another e-book containing ten unexplained words. Their performances were compared to ten unexposed control words. As a whole group, results indicated that teacher's word explanation resulted in greater word learning compared to when word explanation was not provided. However, e-book reading conditions without teacher's word explanation did not lead to incidental word learning from the e-book context compared to the unexposed control words. When the students were divided into subgroups based on their reading abilities, readers with higher reading abilities learned more word meanings from e-book with teacher's word explanation. However, three subgroups of readers showed different patterns of word learning across the e-book with and without word explanation and the control conditions. Educational implications of using e-books for students with different reading abilities and limitations are discussed.