The present study sought to examine the improvement in vocabulary comprehension and retention of Saudi English as foreign language female students at King Abdul Aziz University as a result of integrating YouTube in their reading classes. The study also investigated the perceptions of both students as well as teachers towards the inclusion of YouTube on the development of vocabulary. One hundred female intermediate level students aged between 18-20 years old participated in the study. Students were divided into two groups: an experimental group who watched YouTube during the reading activities and a control group who was not exposed to the videos. Data were collected using pre-tests and post-tests in addition to questionnaires. The findings of the study reveal that the group who viewed the YouTube clips outperformed the group who was not exposed to YouTube videos in the posttest. The results clearly show that YouTube provided statistically significant effects on the students' vocabulary acquisition. The findings of the study indicate that the participants positively viewed the use of YouTube in their lessons. The findings also revealed significant improvement in the students' vocabulary achievement. The implications of the findings are discussed within the context of foreign language learning and teaching.