This study explored the effectiveness of the two computer-assisted modes: cooperative and individual on improving Iranian high school students’ reading comprehension. It was also concerned with investigating the effectiveness of the two computer-assisted modes on the participants’ foreign language learning anxiety (FLLA). The sample of the study consisted of two intact groups, each containing 24 students, which were randomly assigned into a control and an experimental group. The control group completed the study according to the individual computer-assisted learning while the experimental group was taught via computer-assisted cooperative language learning. The participants in the experimental and the control groups, which consisted of 48 female students, took reading comprehension pretest and posttest. They were also given foreign language classroom anxiety scale (FLCAS) questionnaire both at the beginning and at the end of the treatment. The collected data were analyzed using SPSS 16.0. The results of the independent and paired samples t tests indicated that the experimental group, in which cooperative learning was integrated into computer-assisted language learning, outperformed the control group in terms of reading comprehension. In addition, the level of foreign language anxiety improved after the treatment in the experimental group. The findings of this study provide some insights for teachers to consider the integrating of cooperative learning into computer-assisted language learning setting.