Abstract: Abstract Objective:To investigate the characteristics of auditory brainstem response (ABR) in children with global developmental delay (GDD) to assist in early diagnosis of GDD. Methods:GDD refers to the delay in two or more developmental indicators or milestones. Children aged 1 to 4 years who met the GDD diagnostic criteria and received ABR test were enrolled from July 2015 to August 2019 and separated into a GDD group (the developmental quotient of each energy region in Gesell development scale ≤75) and a control group (the developmental quotient of all energy regions＞85). The interval between the test of ABR and Gesell scale should not exceed 2 weeks. The GDD group and the control group are both divided into two subgroups: 1 to 2 years old (≥ 1 year but <3 years) and 3 to 4 years old (≥ 3 years but <5 years).Compare the ABR parameters between the GDD and control group as well as the changes of the ABR parameters between the two age groups. Results:There were 129 children in the GDD group, 83 for 1 to 2 years old and 46 for 3 to 4 years old and 58 in the control group, 45 for 1 to 2 years old and 13 for 3 to 4 years old. Peak latency Ⅲ, Ⅴ and inter-peak latency Ⅲ-Ⅴ, Ⅰ-Ⅴof the GDD group was prolonged when compared with the control group (P<0.05). In the 1-2yr subgroup, peak latency Ⅲ, Ⅴ and inter-peak latency Ⅲ-Ⅴ, Ⅰ-Ⅴof the GDD group was prolonged when compared with the control group (P<0.05). In the 34yr subgroup, interpeak latency Ⅰ-Ⅴof the GDD group was prolonged when compared with the control group (P<0.05). WaveⅤamplitude of the GDD group was reduced when compared with the control group(P<0.05). In the 12yr subgroup, waveⅤamplitude of the GDD group was reduced when compared with control group (P<0.05). In the 3-4yr subgroup, there were no amplitude differences between the GDD and control group. In the GDD group, peak latency Ⅲ, Ⅴand inter-peak latency Ⅰ-Ⅲ, Ⅰ-Ⅴin the 3-4yr subgroup were reduced when compared with the 1-2yr subgroup(P<0.05) and in the control group, no age differences were found in latency and amplitude. Conclusion:GDD children showed brainstem auditory processing abnormalities with prolonged ABR peak latency Ⅲ, Ⅴ, inter-peak latency Ⅲ-Ⅴ, Ⅰ-Ⅴ and reducedⅤamplitude. The younger the GDD children were, the more obvious the ABR abnormalities were. The latency and amplitude gradually caught up to the normal level from the age of 3. Therefore, the ABR test can be used as an objective method to assist in GDD diagnosis but its role in developmental monitoring will be less important with an increase in the age.