Objective To conduct QC activities to reduce the incidence of fluid extravasation in PICU patients. Relieve discomfort in PICU patients,and strengthen the awareness of nurses active service,improve quality of care and management effectiveness. Methods Establishing QC circle,applying the method of PDCA cycle,investigating fluid extravasation in PICU patients,analyzing the main reasons for fluid extravasation,developing countermeasures,Implementing strategies,summarizing and evaluating the effects regularly.Comparing the incidence of fluid extravasation in PICU patients before and after the activity. Results After the activity,the incidence of fluid extravasation decreased from 15.48% to10.44%,the incidence of severe fluid extravasation decreased from 2.38% to 0.55%,P<0.05,the difference was statistically significant. Conclusion The QC activity effectivelycan reduce the incidence of severe fluid extravasation in PICU patients.