This study investigates the effects of shadowing, the oral repetition of what is said right after the language spoken, on L2 listening and speaking abilities of Korean middle school students. It also examines whether shadowing has a positive effect on students’ affective aspects in terms of self-confidence, preference, and perception. The experiment was conducted with 108 middle school students in Gwangju. The participants were divided into three groups, listening only, shadowing only, and listening plus shadowing, and received six weeks of treatment. The data collection consisted of the result of listening tests, speaking tests and questionnaires. The results showed that listening plus shadowing had a positive effect on L2 listening abilities compared to listening only techniques. The results also showed that there was no positive effect of shadowing on L2 speaking abilities. In addition, the results indicated that shadowing increased students’ self-confidence in using English, their shadowing preferences, and the positive perception about the efficacy of shadowing on English speaking skills improvement. This paper therefore argues that shadowing techniques need to be considered as an effective supplementary technique for practicing English listening skills in EFL middle school context.