Purpose: To investigate the continuous effect of nonnutritive sucking(NNS) after stopping NNS on heart rates, oxygen saturation, and behavioral states of premature infants. Method: From December 15, 2004 to February 15, 2005, 20 premature infants hospitalized in neonatal intensive care units were assigned 10 for experimental and 10 for control group. As an experimental treatment, circular pacifiers made vacuous with 2×2 gauzes were used for 5 minutes for 5 days. For the measurement of treatment, heart rates and oxygen saturation were checked every minute for 5 minutes after stopping the NNS and behavioral states were monitored through video recording at the same time in each group. Results: The changes of heart rates and oxygen saturation were shown significant differences according to the time between experimental and control groups. Heart rates were significant interactions between the groups and the time. Quiet awake state on ABSS scores were likely to increasing compared with the control group. Conclusion: I reached this conclusion that NNS is a positive intervention to bring about increased oxygen saturation and decreased heart rates of premature infants for 5 minutes after stopping the NNS, continuously.