Extensive reading (ER) has been shown to be an effective approach in helping second language (L2) students learn to read the target language. Of particular interest is how L2 learners in English for Academic Purposes (EAP) courses that included ER would react to ER since ER involves L2 learners reading easy, interesting books that they select themselves. We examined the reactions of 57 EAP university students to ER. The study was conducted longitudinally for two semesters in Fall 2017 and Spring 2018, where two groups of learners read online books for ten and twelve weeks respectively. We used the Xreading Library, an online subscription-based graded-reader library that allows students unlimited access to more than 1000 books on their computers, tablets or mobile devices. We gathered both quantitative and qualitative data to determine the extent to which online ER affected the learners' attitudes toward reading in English, their academic reading, and English proficiency in general and their instructor' reactions to Xreading. The study revealed that L2 learners' reading attitudes were significantly improved after reading graded readers online. The results also suggested that, in general, the learners felt that their reading rates, vocabulary, grammar, comprehension, writing and speaking were all improved through online ER. Though learners perceived the effects of online ER on their academic reading differently, the instructors held positive attitudes toward online ER. [The page range on the .pdf (p103-125) is incorrect. The correct page range is p103-126.]