The education community has gradually recognized the value of augmented reality (AR) technology and its positive impacts on student learning performance. Still, few studies have proposed specific solutions and results to confirm this phenomenon for first graders in English vocabulary learning. Hence, this research explores the effects of AR apps on first graders' English learning motivation and performance in addition to analyzing the moderating effects of learning styles. For this purpose, the class was divided into the experimental group that used an AR app in learning and a control group that used traditional learning methods. A series of stochastics analyses were carried out. Based on the results, this study finds that incorporating AR apps into English vocabulary learning can significantly improve first graders' motivation and English vocabulary learning performance. The study's findings will be beneficial to educational practitioners and researchers in developing instructional theories, strategies, and materials and improving elementary students' learning motivation and performance.