Background: Globally, diabetes brought an enormous burden to public health resources and the situation of disease burden caused by diabetes in China is especially severe. China is currently facing the dual threat of aging and diabetes, and wearable activity trackers could promote elderly diabetic patients’ physical activity levels and help them to manage blood glucose control. Therefore, examining the influencing factors of elderly patients’ adoption intention is critical as wearing adoption determines actual wearing behaviors. Objective: This study aims to explore the predicting factors of Chinese elderly type 2 diabetic patients’ adoption intention to wearable activity trackers and their actual wearing behavior, using Diffusion of Innovation Theory as the theoretical framework. We hope to provide insights to future interventions using wearable activity trackers as tools to improve patients’ outcome. Methods: Wearable activity trackers were freely distributed to type 2 diabeti