Introduction. The study investigated cardiopulmonary function in breast cancer patients versus healthy control women. Methods. overall, 115 women after breast cancer surgery and 50 healthy controls were included. The outcome measures were spirographic and hemodynamic parameters. Results. Most of the investigated parameters in breast cancer patients were significantly lower than in healthy women. The actual vital capacity (VC) was significantly lower by 0.34 l (p < 0.001), forced vital capacity (FVC) by 0.25 l (p < 0.001), forced expiratory volume in 1 second (FEV1) by 0.26 l (p < 0.001), peak expiratory flow (PEF) by 0.95 l/s (p < 0.001), maximum expiratory flow25 (MEF25) by 0.98 l/s (p < 0.001), maximum expiratory flow50 (MEF50) by 0.65 l/s (p < 0.001), expiratory reserve volume by 0.48 l (p < 0.001), maximal voluntary ventilation by 22.73 l/min (p < 0.001). The percentage of predicted values of VC, FVC, FEV1, PEF, MEF25, and MEF50 was lower by 9.93% (p < 0.001), 7.39% (p < 0.001), 8.87% (p < 0.001), 15.7% (p < 0.001), 18.09% (p < 0.001), and 15.96% (p < 0.001), respectively. As for the cardiovascular system, the actual stroke volume was higher in the control group compared with the main group by 12.20 ml/beat (p < 0.001), stroke index by 8.85 ml/beat/m2 (p < 0.001), cardiac output by 0.87 l/min (p < 0.001), left ventricular work by 0.96 g • m/beat (p < 0.001), LVP by 0.26 W (p < 0.001). Conclusions. Cancer treatment negatively affected most cardiorespiratory parameters. The results support the need for physiotherapy intervention in breast cancer patients after treatment.