According to a survey of 74,000 children and teenagers on mental illness in Beijing and the provinces of Liaoning, Jiangsu, Hunan and Sichuan in May 2021, 17.5 percent of students aged between 6 and 16 suffered from mental illness, including attention deficit hyperactivity disorder, anxiety disorder, oppositional defiant disorder, depressive disorder and tic disorder. The World Health Organization says child- hood and adolescence are critical periods for developing and main- taining social and emotional patterns, and that 10 to 20 percent of the age group worldwide have mental illness, but have not received any significant intervention. Mental illness in many adults started in childhood and it is crucial to pinpoint problems and intervene as early as possible. The survey also showed that depression in children and teenagers is closely connected with social and cultural factors, which means there are problems with family, school or society. Experts said there is an urgent need to address mental illness in young people in China, open more clinics to treat them, increase the number of psy- chiatrists and therapists and raise their salaries.