| 【Abstract】 Objective To explore the core symptoms and behavioral problems of children with subthreshold attention deficit/hyperactivity disorder (ADHD) and the influence of ADHD core symptoms on the behavioral problems of this group. Methods On July to August 2021, 25 children with subthreshold ADHD and 25 normal children were selected from a primary school in Guangzhou. Children's condition were assessed by the parents using Swanson, Nolan and Pelham, version IV scale - parent form (SNAP-IV), Questionnaire-Children with Difficulties (QCD) and Conners Parent Symptom Questionnaire (PSQ). Results ①The inattention, hyperactivity-impulsivity and behavioral problems scores of the children with subthreshold ADHD group were higher than those of the control group (t=2.274~7.771, P<0.05). ② Inattention score of Children with subthreshold ADHD was negatively correlated with QCD total score (r=-0.440, P<0.05), and positively correlated with learning problems (r=0.457, P<0.05). The score of hyperactivity-impulsivity was negatively correlated with anxiety score (r=-0.457, P<0.05), and positively correlated with impulse-hyperactivity score. ③Inattention of Children with subthreshold ADHD had a significant predictive effect on daily behavioral problems, and its predictive effect was 46.8% (b=-0.682, P<0.05). Hyperactivity-impulsivity had a significant predictive effect on anxiety and impulsion hyperactivity, and their predictive effect were 36.7% (b=-0.048, P<0.05) and 42.4% (b=0.690, P<0.01) respectively. Conclusion?Children with subthreshold ADHD have significant attention deficit, hyperactivity-impulsivity and behavioral problems, and attention deficit may be the main cause of their daily behavioral problems.