Objective:To investigate the application value of standard operation procedure (SOP) of thoracentesis in clinical skills training for undergraduates.Methods:In this study, 63 undergraduates were randomized into two groups, with 29 students in experimental group receiving SOP training, and 34 students in control group trained by traditional teaching methods. The performance of the two groups at different stages of thoracentesis were compared after the training. SPSS 19.0 was used to analyze the assessment data.Results:The experimental group was significantly superior to the control group in the stages of "puncture operation" and "post-puncture operation" [(33.76±2.46) points vs. (31.91±3.60) points, P=0.02; (7.93±1.53) points vs. (6.79±1.84) points, P=0.01], as well as the total scores [(82.59±4.14) points vs. (79.26±4.94) points, P=0.01]. Conclusion:It's suggested that application of SOP may improve the effectiveness of thoracentesis training, and organized teaching methods are essential for clinical skills training.