The purpose of this study was to examine differences between male and female in heart rate due to 93% oxygen administration of the three levels (1L/min, 3L/min, and 5L/min). Ten healthy male (25.0$pm$1.8years) and ten female (23.7$pm$1.9years) college students were selected as the subjects for this study. The experiment consisted of three runs, i.e., the three levels of 93% oxygen administration, respectively. The each run consisted of three phases, i.e., Rest 1 (5min), Hyperoxia (10min), and Rest 2 (5min). Heart rate was measured throughout the three phases. Heart rate was decreased during hyperoxia compared to Rest 1 and 2. By increasing the supply rate of highly concentrated oxygen, ${Delta}1$ (decreasing rate of heart rate during hyperoxia compared to Rest 1) was increased. And ${Delta}2$ (decreasing rate of heart rate during hyperoxia compared to Rest 2) of male was lower than female, regardless of supply rate.