The advancement of technology has provided new avenues for English language teachers to assist students in improving their language learning processes. Augmented reality is an emerging technology that can implement virtual objects into the physical learning environment. This quantitative study aimed to determine the impact of employing augmented reality in a CLIL lesson. The study also looks at EFL learners' attitudes about the use of AR. For this purpose, 76 high school students (38 males and 38 females) have taken part in this study. The results showed that using an AR-based mobile application improved the language achievements of the learners. The learners who used AR have gathered better results in the CLIL lesson. Additionally, the learners had positive attitudes towards the use of augmented reality. They found it satisfying and engaging and were willing to use it in the future again. Based on the study findings, EFL teachers are encouraged to use AR in their classes to teach both content and the language.