Objective To investigate the effects of acupoint injection of mouse nerve growth factor (mNGF) on treatment of children with autistic spectrum disorders in different age groups. Methods Totally 80 cases of children with autistic spectrum disorders were divided into control group and experiment group according to random number table method, with 40 cases in each group. The control group was given structured education, ABA behavioral training, sensory integration training, and language training, 30 min for each class, 4 h each day, 5 d a week, for 5 months. At the same time, the control group was also given head needling treatment, once every other day, 3 times a week, 30 times as one treatment course, 2 courses. On the basis of the treatment of the control group, experiment group was given mNGF through acupoint injection, once every other day, 3 times a week, 10 times as one treatment course, 10 d between each treatment course, 5 courses in total. The scores of autism behavior checklist (ABC), children autism and related developmental disorders psychological education rating scale-Chinese version (C-PEP), neuropsychological development scale among children aged 0–6 years in the two groups were compared. Results Compared with before treatment, ABC scores in both group after treatment decreased significantly (P<0.05); ABC scores after treatment in children aged 18–36 months and 37–54 months in the experiment group were lower than those of the control group (P<0.05). Neuropsychological development scale scores in children aged 18–36 months and 37–54 months were better than the control group (P<0.05). Compared with before treatment, C-PEP scores of both groups increased significantly (P<0.05). There was statistical difference in the C-PEP scores in children aged 18–36 months between the two groups after treatment (P<0.05). The C-PEP scores in children aged 18–36 months increased to the highest (P<0.05).Conclusion Acupoint injection of mNGF can improve the clinical symptoms and intelligence of ASD children of all ages, but children can receive better treatment effects at younger ages.