Preterm birth is the leading cause of death for children under one year of age, and the main reason for the child to enter the incubator. Despite medical advances and technical winning in the care of premature infants., but they are exposed in Nursery Ward for environment stimuli not compatible with their level of developmental and evolutionary such as high levels of light and the noise that exceed the recommended levels in Nursery Ward. This leads to stress reactions by premature immature systems. demonstrating in one of their faces instability in vital indicators especially heart rate and oxygenation which may submit him for a short or long-term injuries . Aim of the study: Determine the effect of reducing the level of light and noise intensity in environment of Nursery Ward on the heart rate and oxygenation for premature infants. Materials & Methods: This true experimental design study of before and after on a sample of 30 premature acceptable in the Nursery Ward in Albasel Hospital in Tartous. they were selected in simple random way. Data were collected using a list to record demographic and health information for the mother and premature. reads of light-meter and noise-meter sitting beside the premature incubator, and reads of Oxy-meter connected to the premature wrist. was taken to every 5 minutes in each phase of the four phases, 60 minutes for each one, and conducted in the same day.1) Non intervention phase. 2) reduce light Intensity without noise Intensity reduction phase.3) reduce noise Intensity without light Intensity reduction phase.4) reduce light and noise Intensity together phase. These data were collected and analyzed using appropriate statistical programs. Results: This study showed a significant decrease in the mean of heart rate and a significant increase in the mean of oxygenation in the last three phases, compared with means in the first phase. This reduction and increase in the means was larger significantly in the fourth stage compared with the second and third phases. That because reducing light and noise will reduce its physiological stress to premature thus lower the pulse rate and increasing oxygenation. We can thus reduce the use of light and noise measures to improve the care environment for premature.