Objective: To understand changes of physical fitness, among college freshmen in one college in Xi an from 2005 to 2018. Methods: Body mass index (BMI), vital lung capacity and cardiorespiratory endurance test data from 47 047 freshmen from 2005 to 2018 were included and analyzed. BMI, vital lung capacity, and cardiorespiratory endurance were classified according to the National Student Physical Fitness and Health Standard. Descriptive statistics, t test was used in the data analysis. Results: Mean BMI, vital lung capacity and cardiorespiratory endurance for male and female were (21.69±3.26) (20.88±2.65) kg/m 2, (4 189.87±788.57) (2 815.06±572.07) mL, (246.17±24.09) (239.97±20.23) s, respectively, all of which had significant statistical differences (t=29.48, 218.87, 28.70, P<0.05). Physical fitness indicators showed significant differences over the years (F=104.82, 185.43, 40 891.99, P<0.05). Mean BMI and vital lung capacity in male and female freshmen showed nonlinear increase trend across the past 14 years, while endurance showed a "V"shaped change with a significant inflection point in the year of 2009. Conclusion From 2005 to 2018, BMI and vital lung capacity showed an upward trend, and cardiorespiratory endurance quality continued to decline since 2009 among college freshmen.