In this study, achievement, attitude and cognitive load levels of students in learning English by Augmented Reality (AR) is examined. Within this context, it is researched whether cognitive load and attitudes of students differ according to the achievement levels of students or not and the correlation between these variables were revealed. In the study, casual-comparative and correlational methods were used. The sample of the study is composed of 122 fifth-grade students (66 males and 56 females) from 5 different secondary schools in Erzurum. In data analysis, descriptive and inferential analysis methods were used. As the result of the study, it is found that secondary school students are pleased with learning English by the aid of AR, they have a low anxiety level and they want such applications to be used their courses in future. Moreover, it is found that the cognitive load levels of students in the process of self-directed learning in AR environment are low. Another important finding of the study is that the attitudes of successful students are significantly higher than others. In addition, the relationships between attitude, achievement and cognitive load levels were revealed in detail.