Cognitive is an essential developmental aspect for children. The cognitive barrier is one of the learning barriers experienced by children with autism. From educational perspective, teacher language input can appropriately develop cognitive abilities of autistic students. This study aims to describe (1) teacher's language input for recognizing the cognitive abilities of autistic students in classroom interactions and (2) cognitive abilities of autistic students based on teacher language input in classroom interactions. The approach of the study was conducted qualitatively with case study, while source of data was oral texts from the teacher language input toward autistic students in classroom. The results shows that the cognitive abilities of autistic students can be recognized through teacher's language input in classroom learning by engaging interrogative speech acts, such as representative, directive, expressive, and commissive. The cognitive level is used to see the variants of the teacher's language input. Meanwhile, the acquisition of students' cognitive abilities based on teacher language's input is developed through memorizing, understanding, applying, and analyzing skills with criteria student A and B in the medium category, and G in low category.