This study was conducted to examine the effect of asynchronous computer-mediated condition on L2 learners' speaking ability, speaking apprehension, L2 self-confidence, and willingness to communicate. The participants of this study included 40 intermediate undergraduate students of English language teaching at an Iranian university. The participants were assigned to two experimental (asynchronous computer-mediated) and control (face-to-face) conditions randomly. In the experimental group, the participants practiced speaking in an asynchronous online environment, and in the control group, the students spent a part of their class time accomplishing monologue tasks. Using questionnaires, the participants' speaking ability, speaking apprehension, L2 self-confidence, and willingness to communicate were measured at the beginning and at the end of the term. The findings showed that the monologue speaking ability mean score of those in the computer-mediated group improved significantly more than that of the face-to-face group. Another finding of this study was the superiority of the computer-mediated condition with regard to the participants' speaking self-confidence, speaking apprehension, and willingness to communicate. Overall, the results suggest that asynchronous computer-mediated condition can provide learners with a less-threatening condition that can improve the chances of their L2 monologue speaking ability. Manuscript profile