The aim of the study is to determine the effects of using TV series to improve EFL students' listening achievement levels in English. Another aim of the study was to reveal the perceptions of EFL students about the use of TV series in English to improve their listening proficiency. To this end, the study was conducted as a mix-method study that includes 30 EFL students. The participants of the study were chosen via convenience sampling. The data of the study were collected through pre-and post-achievement tests, a questionnaire and semi-structured interviews. While the data acquired via pre and post-tests and questionnaires were analyzed by using SPSS 25 Statistical Package, the data obtained through semi-structured interviews were examined by adopting a categorical-content analysis approach. The study results uncovered that the use of English TV series improved EFL students' listening achievement levels. It was also revealed the fact that EFL students thought that watching TV series contributed to their success in the classroom, and they believed that watching TV series in English improved their listening comprehension. The results of the study also showed that TV series could catch the learners' interest, and they can positively affect their motivation to improve their listening proficiency.