This study investigated effectiveness of Web-based CALL on listening comprehension. Both students' academic performance and attitudes were examined. T-tests were used to analyze the results of students' academic performance. Descriptive statistics interpreted students' attitudes toward this learning. Students' participation was also recorded. Although the Web-based CALL was not found to improve students' listening comprehension, students responded to the Web-based CALL positively and the lower-level students, compared to their higher-level peers, were more motivated to practice listening comprehension under the Web-based CALL environment. This paper ends with discussions of potential issues and recommendations for future implementation and studies. (Contains 4 tables and 1 figure.)