The present study was intended to explore EFL studentsí perceptions of learning vocabulary collaboratively with computers. We recruited 91 eighth-graders from three intact classes in a junior high school in Taiwan, assigning one class to learning individually without computers, another learning collaboratively without computers and the other learning collaboratively with computers. All participants took a pretest before three sets of vocabulary exercises in three periods; after each set, they took an immediate posttest; and, a month after the experiment, all took a delayed posttest. The computer group also completed a questionnaire and six students were interviewed. The quantitative data showed that students, learning collaboratively with computers, were not outperformed in vocabulary tests designed for individual study; however, they showed better retention, outperforming the others in the delayed posttest. From the qualitative data, more than 70% of the participants in the computer group reported a positive attitude and anticipation to learning vocabulary in such an environment. A further analysis found the nature of tasks, sharing of computers and grouping effective to their approaches to learning. Finally this study agrees that success is not guaranteed but deliberate design needs to be considered before learners are engaged in a computer-supported collaborative learning environment.