Abstract: In order to explore the effect of isoflurane anesthesia at different concentrations on plasma renin-angiotensin-aldosterone system（RAAS） and hemodynamics in Polish rabbits, the experiment randomly divided 18 healthy Polish rabbits into the isoflurane low concentration group（L-ISO group, 1% isoflurane anesthesia）, medium concentration group（M-ISO group, 3% isoflurane anesthesia）, and high concentration group（H-ISO group, 5% isoflurane anesthesia）; the anesthesia lasted for 20 min, and the anesthetic effect on Polish rabbits was observed. Body temperature（T）, heart rate（HR）, oxygen saturation（SpO₂）, respiratory rate（RR）, systolic blood pressure（SAP）, diastolic blood pressure（DAP）, and mean arterial pressure（MAP） of Polish rabbits in each group were monitored before isoflurane anesthesia（0 min）, 5, 10, 15, 20 min after anesthesia and 10 min after recovery. Blood from the femoral artery was collected simultaneously to detect the plasma levels of Renin, angiotensin Ⅱ（ANG-Ⅱ）, and aldosterone（ALD） and to analyze the correlation between the levels of Renin, ANG-Ⅱ, and ALD with SAP, DAP, and MAP. The results showed that T at 15, 20 min after anesthesia was significantly lower than that at 0 min in each group（P＜0.05）. HR and RR at 5, 10, 15, 20 min after anesthesia were significantly lower than those at 0 min in each group（P＜0.05）. SpO₂ at 15, 20 min was significantly lower than that at 0 min in the H-ISO group（P＜0.05）. SAP, DAP and MAP at 5, 10, 15, 20 min after anesthesia were significantly lower than those at 0 min in each group（P＜0.05）. The levels of Renin, ANG-Ⅱ and ALD at 5, 10, 15, and 20 min after anesthesia were significantly lower than those at 0 min in the M-ISO and H-ISO groups（P＜0.05）; the levels of Renin and ALD at 20 min after anesthesia were significantly lower than those at 0 min in the L-ISO group（P＜0.05）. T in the H-ISO group was significantly lower than that in the L-ISO and M-ISO groups at 10, 15, 20 min（P＜0.05）. HR and RR in the H-ISO group were significantly lower than those in the L-ISO and M-ISO groups at 15 and 20 min（P＜0.05）. SAP in the H-ISO group was significantly lower than that in the L-ISO and M-ISO groups at 5, 10, and 15 min after anesthesia（P＜0.05）. DAP in the H-ISO and M-ISO groups was significantly lower than that in the L-ISO group at 5 min after anesthesia（P＜0.05）, and was significantly lower in the H-ISO group than that in the L-ISO group at 10 min after anesthesia（P＜0.05）. MAP in the H-ISO and M-ISO groups was significantly lower than that in the L-ISO group at 5, 10 min after anesthesia（P＜0.05）, and was significantly lower in the H-ISO group than that in the L-ISO group at 15 min after anesthesia（P＜0.05）. SAP in the H-ISO group was significantly lower than that in the L-ISO group at 10 min after recovery（P＜0.05）. DAP and MAP in the H-ISO group were significantly lower than those in the L-ISO and M-ISO groups at 10 min after recovery（P＜0.05）. Renin and ALD contents at 5,10,15,20 min and ANG-Ⅱ contents at 15,20 min in the H-ISO and M-ISO groups were significantly lower than that in the L-ISO group after anesthesia（P＜0.05）. ALD content decreased significantly with the increase of isoflurane concentration in three groups at 5, 10, 15, 20 min after anesthesia（P＜0.05）. The contents of Renin, ANG-Ⅱ and ALD in the M-ISO group were significantly correlated with SAP, DAP and MAP（P＜0.01）, while SAP, DAP and MAP in the L-ISO and H-ISO groups were less correlated with the contents of Renin, ANG-Ⅱ and ALD. The results suggested that different concentrations of isoflurane anesthesia could cause changes in physiological indexes, hemodynamics and RAAS system in Polish rabbits. 3% concentration of isoflurane anesthesia to Polish rabbits was the best, which caused the changes of the contents of Renin, ANG-Ⅱ and ALD in plasma which involved in the regulation of hemodynamic indexes in Polish rabbits.