Objective To investigate the application of fundamental cause in the preparation of surgical instruments.Methods The fundamental cause analysis method was used to analyze the situations of improper preparation of surgical instruments in the operation room to analyze the fundamental causes and work out countermeasures.The preparation of surgical instruments before and after the implementation was compared.Result The qualification rate of surgical instruments increased from 96.0％ before the implementation to 98.6％ after the implementation,with statistically significant difference (P＜0.001).Conclusion The fundamental cause analysis can help the operation room to find out the problems in the surgical equipment preparation process so as to improve the working procedures and the qualification rate of prepared surgical instruments.