Objective To observe the changes and influencing factors on pulse oxygen saturation and hemoglobin in Tibetan residents of 4 200 meters above sea level. Methods The health examination data of the Tibetan village residents were collected in Rerong Country, Shannan Prefecture of Tibet autonomous region from January 4 to February 4, 2012. And the information of pulse oxygen saturation was recorded at the same time. The residents were categorized by sex, age and smoking history to observe the difference in each group. Results The clinical data of 234 healthy Tibetan residents were collected with average age of (37.9±13.9) years old, and 97 were male (41.5%). There were no difference in pulse oxygen saturation [(86.1±3.4)% and (86.0±4.7)%, P=0.784) between male and female residents, and heart rate of the male was less than that of the female [(77.9±9.8) bpm and (81.1±12.1) bpm, P=0.036], while the hemoglobin content was higher in male residents [(164.5±15.4) g/L and (139.1±19.2) g/L, P=0.000). With the increase of age, especially in the group older than 60 years, the pulse oxygen saturation significantly decreased (P=0.003), while hemoglobin content showed a gradual increase trend (P=0.000). And in the group which smoking history more than 20 pack-years, the pulse oxygen saturation was lesser than the other groups, and the hemoglobin content increased (P=0.000). Conclusions The pulse oxygen saturation level of Tibetan residents of 4 200 meters above sea level is negatively correlated with age and smoking history, and the level of hemoglobin is positively correlated with age and smoking history. In resting state, there is no significant difference in heart rate between the groups divided by ages.