Abstract: OBJECTIVE To investigate the effect of salidroside(SDS) on the expression of transforming growth factor-β1 (TGF-β1) in lung tissue of acute paraquat(PQ) poisoned rats. METHODS All of 130 SD rats were randomly divided into normal control group, model group and SDS group, the latter two groups were then divided into 1, 3, 7, 14, 21, 28 d group. The rats of model group and SDS group were given a single dose of PQ(20 mg·mL^-1) intraperitoneally to induce lung injury, and after 1 h, the same volume of saline and SDS(10 mg·kg^-1) was intragastricly administrated respectively per 12 h. The rats were executed in each time point, and use methods of immune histochemistry and real-time PCR to observe the TGF-β1 expression of both protein and mRNA level. RESULTS The expression of TGF-β1 in model group and SDS group were significantly increased compared with normal control group, and peaked at 7 d after injectd PQ intraperitoneally. Compared with model group, the expression of TGF-β1 was lower in different time points(P<0.05). The level of TGF-β1 mRNA was increased at the first day, peaked at the 14th day and then returned to normal at the 28th day. Compared with model group, the level TGF-β1 mRNA was lower in SDS group from the 3th day to 28th day(P<0.05). CONCLUSION TGF-β1 is involved in the pathological and physiological process of pulmonary fibrosis. SDS can inhibit its expression, and alleviate the lung injury induced by PQ.