Background and Objectives: Tobacco contains carcinogens, such as nitrosamine ketone (NNK), which play a role in induction of lung cancer through stimulation of vascular endothelial growth factor (VEGF) expression. The aim of this study was to investigate changes in resting levels of VEGF in lung tissues of rats exposed to nicotine-derived NNK following 12 weeks of aerobic submaximal swimming exercise.   Methods: In this experimental study, 46 mature Wistar rats, were randomly divided into five groups, including: exercise, exercise + NNK, NNK, solvent, and control. The groups induced by NNK, received NNK subcutaneously once per week at a rate of 12.5mg/kg body weight for 12 weeks. The training groups performed submaximal swimming exercise for 12 weeks. The levels of VEGF in homogenized lung tissue were measured by ELISA. Data analysis was performed using one-way ANOVA and Tukey's tests at a significance level of p≤0.05.   Results: In this study, a period of swimming training program significantly decreased the levels of VEGF in lung tissue compared to control (p=0.039) and NNK (p≤0.001) groups. A significant reduction was also observed in the VEGF level in exercise + NNK group compared to NNK group (p≤0.001). Furthermore, VEGF levels significantly increased in NNK group compared to exercise (p≤0.001), exercise+NNK (p≤0.001), and solvents (p≤0.001) groups.   Conclusion: Overall, it can be concluded that regular submaximal aerobic exercise plays an effective role in the inhibition of NNK-induced lung