Objective To explore the EEG characteristics and the correlation between EEG characteristics and visual attention function in attention deficit/hyperactivity disorder(ADHD).Methods 1:1 case-control study wag applied(37 ADHD children were compared with 37 healthy control groups).Participants aged from 6 to 14 years were involved in this study.All children were tested EEG characteristics and visual function,including the frequency,amplitude,relative power and counting missing features test.And the correlation was analyzed between relative power and visual function.Results The θ amplitude((20.48±14.99μV)in ADHD wag significantly higher than that in the control group((12.37±8.06)μV),(P<0.05);the β frequency((16.63±1.72)Hz) in ADHD was significantly lower than that in the control group((16.63±1.72)Hz,P<0.05);the relative power of β in ADHD(5.24±1.24)was significantly lower than that in the control group(6.30±1.19),(P<0.05);the θ/β ratio in ADHD(4.22±1.26)was significantly higher than that in the control group(3.41±0.52)(P<0.05);the double eyes'counting missing features mark(56.76±19.16),(49.73±23.39) in ADHD were significantly lower than that in the control group(72.43 ±17.23),(71.35±16.69).There wag significant negative correlation between the θ relative power and double eyes'counting missing features(r=-0.448 and-0.361);the θ/β ratio had significantly negative correlation with the fight eye's counting missing features(r=-0.352).Conclusion Compare to the normal control group,the ADHD group shows significant difference in EEG characteristics and visual attention function.The change of EEG power characteristics hag a significant affect on the allocation of attention.