The development of Augmented Reality (AR) technology has proliferated in the educational arena. The results of subjective observations of engineering mechanics learning show the decline in student interest and understanding caused by conventional teaching methods, which are the biggest obstacles in the learning process, thus impacting students’ cognitive abilities. This study develops AR as an instructional media for engineering mechanics using the Analyse, State, Select, Utilise, Require, and Evaluate (ASSURE) instructional design model with an R&D approach. This study used performance assessment instruments, questionnaires, and interviews with students and lecturers as the primary data. The subjects of this study were 103 students of Mechanical Engineering Vocational Education at Universitas Negeri Padang in the 2020–2021 academic year. The results showed that the use of AR-based learning media had a positive impact on students’ understanding of basic concepts and skills. In addition, AR media support independent learning and provide direct feedback to students. The acquisition of validation results from material experts is 88.48% (very valid), media experts of 89.26% (very valid), and linguists of 87.41% (very valid). The average practicality test results from the lecturer’s responses were 89.70% (very practical) and 81.63% (practical) student responses. In conclusion, the results of developing mobile AR applications that are declared valid and practical can provide a more interactive and exciting learning experience for students to increase their interest and understanding of learning. Therefore, mobile AR is an exciting option for further integrating engineering education into higher education.