In the study, subjects were 40 English major freshmen in a private university in South Taiwan, including 15 males and 25 females. They were required to do some on-line assignments of English listening and reading every week. The research instruments included the Perceptual Learning Style Preferences Survey (Reid, 1998) and a set of General English Proficiency Test (CEF, B1). In addition, students' College Entrance Exam Scores and academic transcripts were used as their prior knowledge and learning outcome. Findings showed that the time students spent on the Web-based educational resources had a great impact on their learning outcome, both in English proficiency and academic performance. However, the factor related to the time they spent on the Web-based educational resources was learning style preferences. In particular, those individual style learners perform better than others. Some implications about using appropriate Web-based educational resources, helping students raise self-awareness of their learning styles and providing style-based strategies in teaching will be discussed