This experimental design study examined the effects of viewing captioned instructional videos on EFL learners' content comprehension, vocabulary acquisition and language proficiency. It also examined the participants' perception of viewing the captioned instructional videos. The 92 EFL students in two classes, who were undertaking the "Tape and Video Interpretation" course, participated in this study. The randomly assigned experimental class viewed 30 episodes of captioned "Connect with English" and the control class viewed the same episodes without captions. Adopting the quantitative approach, a Michigan English Test, Content-Specific Tests and a questionnaire were administered to examine the participants' content comprehension, vocabulary acquisition and language proficiency development as well as the experimental group's perception towards viewing captioned instructional videos. Although, both groups recorded gains, the findings were in favor of the use of captioned instructional videos. The results showed that the effects of viewing captioned instructional videos are greater on vocabulary acquisition and language proficiency development than on content comprehension. The participants' perceptions of the use of captioned instructional video were consistent with the results. They felt that it enhanced their language learning, but did not affect their comprehension of the movie and that captions were not a form of distraction. Pedagogical implications for EFL instructions, especially where multimedia technology tools may be limited is that, captioned instructional videos can be deemed as a promising media to enhance language learning.