The purpose of this study is to investigate the English reading ability of e-learners and the effects of the e-learners’ learning background characteristics on their English reading ability. To achieve these goals, an English reading diagnostic test of 9 subskills was developed and administered to 274 Korean online university students. Before this, however, a survey was conducted about the characteristics of their English learning backgrounds. The results of the study are as follows. First, the e-learners were not proficient at English reading. Second, the e-learners had a low ability to infer information that was not presented directly in the test. Third, lengthy visits to English-speaking countries, prolonged use of English audio-visual materials, frequent writing and reading, as well as long conversations with English native speakers were helpful to improve English reading skills. The results suggest that e-learners need to make a lot of effort to improve their reading ability and that proper feedback and remedial learning are necessary for those with weaker reading ability.