Objective: To observe cardiovascular responses to positive pressure breathing (PPB) using different counter pressures. Method: Cardiovascular responses of 7 male healthy subjects (aged 18-20 years) wearing two kinds of Jerkin-G-suit were observed under three levels of ground-level PPB (30, 50, 70 mmHg) for 3 min. Result: All subjects completed the experiment successfully. While during PPB at 50, 70 mmHg levels within 3 min, HR, MAP, TPR elevated significantly, while SV declined significantly. At all 3 PPB levels Q-Z time was not significantly changed. There were significant difference (P<0.05) between delta SV and delta TPR with the two Jerkin-G-suits under PPB of 70 mmHg. Conclusion: PPB resulted in elevation of MAP, TPR, HR and decline of SV significantly using two kinds of Jerkin-G-suit. PPB had no effect on contractile function of cardiac muscle. Under PPB, SV increased significantly when chest counter pressure was equal to the mask pressure.