Global developmental delay is generally defined as abnormal development in the areas of gross motor, fine motor, adaptive, language, and personal socialization in children 5 years of age or younger. The causes of global developmental delay include genetics, intrauterine dysplasia, chromosomal abnormalities (e.g., Down syndrome), endocrine metabolic diseases (e.g., diabetes mellitus), bone diseases (e.g., osteochondrodysplasia), and chronic illnesses (e.g., cancer), etc. The patients will show developmental backwardness in many aspects, and their height, weight, and head circumference measurements will all be on the low side. The treatment of overall developmental delay is based on symptomatic treatment and active rehabilitation. Some patients can be cured through active symptomatic treatment, but some of them will still have the sequelae of developmental delay. Patients need to pay attention to life management, psychological management, ensuring sufficient sleep, exercise management and diet management in daily life. If the diagnosis of overall developmental delay is confirmed, the treatment should be standardized in accordance with medical advice.