① The name was changed from generalized developmental disorder to autism spectrum disorder;

② Classification changes Autism, Asperger's disease, other unspecified generalized developmental disorders, childhood disintegration disorder and Rett'sdisorder in DSM-4 are no longer used, while autism spectrum disorder covers the first four items in DSM-5, and Rett'sdisorder is no longer classified as autism spectrum disorder.

③ Changes of symptoms in the core diagnosis: From social, verbal and stereotyped behaviors in DSM-4 to social and stereotyped behaviors, since the original three-dimensional two groups of symptoms, language communication disorder and social communication disorder are actually inseparable, it is more accurate to identify them as one group of symptoms. DSM-5 requires that the diagnosis of autism spectrum disorder must have two core symptoms.

(4) Compared with DSM-4, DSM-5 increases the diagnostic criteria of sensory perception.

⑤ The onset time is relaxed from the original definition of onset before the age of three to "manifested in the early stage of development", especially pointing out that "the challenge of social communication may not be fully presented until it exceeds its limited ability".

⑥DSM-5 formally put forward the degree division of autism spectrum disorder, based on the degree of support that individuals need.