The study explored the effects of students' locus of control and types of control over instruction on their self-efficacy and performance in a web-based language learning environment. A web-based interactive instructional program focusing on the comprehension of news articles for English language learners was developed in two versions: learner- and program-control. Following the web-based learning, the participants completed a content comprehension test and self-report measure of self-efficacy. Results showed that: (1) students with an internal locus of control performed better on the test and the self-efficacy measure than those with an external locus of control; (2) students learning from the learner-control version of the web-based instruction performed better on the test and the measure of self-efficacy than those learning from the program-control version; (3) students with an internal locus of control who learned from the learner-control version got the highest score on the test and the measure of self-efficacy, while students with an external locus of control who learned from the program-control version received the lowest score on the test and the measure of self-efficacy; and (4) students with an external locus of control who learned from the learner-control version outperformed students with an internal locus of control who learned from the program-control version on both academic performance and the measure of self-efficacy. (Contains 6 tables and 3 figures.)