The purpose of this exploratory descriptive study §was to examine relationships between stress §physiological signals and stress behaviors in §preterm infants during periods of environmental §stress. Research used a prospective, quasi-§experimental repeated-measuring method to examine §the research variables in one group of preterm §infants. Measurements of research variables were §recorded every two minutes during two 60-minute §observation periods and conducted over two days. The §multiple linear regression of GEE methods were used §to approach the relationships between stress §physiological signals and stress behavioral §responses. The convenience samples were preterm §infants and all research subjects were in the §incubator in NICU or sick baby room. Research data §were 4164 observations of 37 preterm infants. There §was a statistically significant relationship between §nine stress behavioral responses and changes in §heart rate and respiratory rate. There was also a §statistically significant relationship between 11 §stress behavioral responses and changes in oxygen §saturation level.