The purpose of the present study was to investigate friendship establishment behaviors among students with a combination of autism spectrum disorders and intellectual disabilities in special needs classrooms by analyzing the differences of social interactions with other students with a combination of autism spectrum disorders and intellectual disabilities, those with intellectual disabilities, and their teachers. As a result of the observation, Student A, who is a person with a combination of autism spectrum disorder and intellectual disability, was rarely observed to start friendship establishment behaviors with Students B and C, who also are people with a combination of autism spectrum disorders and intellectual disabilities, however, those behaviors between Students B and C were frequently observed. This difficulty in the establishment of social interactions occurred in Student A was considered to be the cause of age differences: Student A was older than the other two students. In addition, the frequency of these students’ social interactions with adults was higher than that of their interactions with peers. Previous studies revealed that the frequency of starting social interactions between pairs with children with a combination of autism spectrum disorders and intellectual disabilities was lower than that of interactions between children with a combination of autism spectrum disorders and intellectual disabilities and those with intellectual disabilities. However, in the present study, it was found out that the frequency of social interactions from students with a combination of autism spectrum disorders and intellectual disabilities to those with intellectual disabilities was less than that of interactions from students with a combination of autism spectrum disorders and intellectual disabilities to those with intellectual disabilities.