Autism spectrum disorders（ASD）are developmental disorders that have social communication deficits as a core symptom. Even adults with high‒functioning ASD have difficulties in social communication and, therefore, have deficits in understanding others’ minds. Recent research has found that they are unable to understand not only others’ minds, but also their own minds. This could lead to difficulties in self‒regulation. Some studies have reported the effectiveness of cognitive‒behavioral therapy（CBT）in improving self‒regulation, especially in reducing anxiety in children and teenagers with ASD. However, few studies have examined adults with ASD. Therefore, this study investigated the efficacy of group‒based CBT for adults with ASD. Our hypothesis is that adults with ASD can understand their own emotions, exercise self‒regulation, and thus alleviate their own secondary symptoms, such as anxiety and depression. The study is a randomized open‒blind study with centralization using minimization and blind assessors. In this paper, we introduce the protocol for this study and examine the characteristics and adaptive problems of people with subthreshold ASD interested in joining this study.