Cardiorespiratory fitness is an indicator of a person's fitness and a predictor of cardiometabolic diseases such as diabetes mellitus, coronary heart disease, and stroke. One of the organs that play a role in cardiorespiratory fitness is the lungs. Thus, lung function has the potential to be a predictor of cardiorespiratory fitness. This study aims to determine the relationship between lung function and the level of cardiorespiratory fitness in students of the Faculty of Medicine, Jenderal Soedirman University. As many as 29 male subjects aged 18-25 years became research subjects. The consecutive sampling technique was used to recruit the subjects. Lung function was measured by spirometry to determine the value of Forced Vital Capacity (FVC), Force Expiratory Volume in 1 second (FEV1), and the FEV1/FVC ratio. The average predicted percent value of FVC, FEV1 predicted percent value, FEV1/FVC ratio, and the mean cardiorespiratory fitness index in subjects were 80.82 ± 2.72%; 87.17±2.71%; 94.87±0.63%; 65.88±3.575, respectively. The Pearson correlation test showed no relationship between FVC, FEV1, and the FEV1/FVC ratio on cardiorespiratory fitness, with p values ​​of 0.324; 0.284; and 0.231 (p>0.05), respectively. In conclusion, there is no relationship between lung function and the level of cardiorespiratory fitness in students of the Faculty of Medicine, Jenderal Soedirman University