In this study, it was aimed to determine the effect of activities based on augmented reality applications in 9th grade biology lesson on students' achievement and motivation towards biology lesson and to get students' opinions about the applications. In the study, mixed method was used. The study group of the research consisted of students of two different classes at the 9th grade level of a private high school located in the city center of Karaman in the 2018-2019 academic year. When the research findings were examined, it was seen that the academic achievement post-test mean scores of the experimental group students were found to be significantly higher than the mean scores of the control group students. According to another finding of the study, there was no significant difference between the experimental group and the control group students in terms of the total mean scores obtained from the motivation questionnaire for biology lesson. However, a significant difference was found in favor of the experimental group in terms of "anxiety in exams" dimension. As a result of the research, the students stated that they liked the biology lessons in which augmented reality applications were carried out, that augmented reality applications made abstract concepts concrete and made them more permanent, and that the lessons conducted in this way were fun.