Objective To explore the effective model to improve the skill of tracheal intubation and solve the trainees' skill heterogeneity.Methods Fourty-two trainees who scheduled for training in endotracheal intubation skills at Department of Anesthesiology,Peking University Third Hospital,during August 2016 to August 2017 were randomly divided into step-by-step training model group (n=21) and the traditional training model group (n=21).The endotracheal intubation skill of the two groups of trainees were assessed before and after the one year study.A questionnaire survey was conducted to obtain the satisfaction degree of the trainees in the two groups.Results The endotracheal intubation assessment score of step-by-step training model group and traditional training model group before the study were (52.8 ± 10.7,53.1 ± 11.2,t=0.092,P＞0.05),after the different model training,the score were (89.4±3.7,77.1 ± 6.5,t=-7.526,P＜0.05),the questionnaire survey showed that the trainees in the step-by-step training model group consider that the step-by-step training model is more favorable than the traditional training model in improving the teaching effect of endotracheal intubation.Conclusions The step-by-step training model can improve the trainees skill of tracheal intubation and solve the skill heterogeneity due to the different trainees source and ability.