Objective To evaluate the effect of situational leadership theory training on head nurses’ leadership style in nursing management, and summarize the application methods of situational leadership theory. Methods In December 2013, by means of convenience cluster sampling method, 154 head nurses of West China Hospital of Sichuan University were selected for a Leadership Style Self-rating Questionnaire survey, of whom 84 attended the situational leadership theory training one month ago. The questionnaire score was compared between the trained head nurses (the trained group) and the non-trained ones (the non-trained group). Results A total of 154 questionnaires were issued, and 109 valid ones were recovered, in whom 72 were trained by the situational leadership theory while the other 37 were not. The average scores of head nurses’ flexibility and efficacy in the trained group (22.35±5.12 and 55.67±7.59) were higher than those in the non-trained group (19.03±4.05 and 50.95±5.30), and the proportions of head nurses with high flexibility and high efficacy in the trained group (61.1% and 31.9%) were higher than those in the non-trained group (32.4% and 8.1%), and the differences above were statistically significant (P<0.05). Conclusions The training of the situational leadership theory can improve the application of theory to clinical nursing management and promote the head nurses’ flexibility and efficacy to accelerate their work enthusiasm and personal improvement. It can also promote team cohesion and sense of accomplishment by creating a positive team atmosphere to make the efficient usage of limited human resources.