Objective：To study specific mechanisms of activation of mouse hepatic stellate cells（mHSCs） by transforming growth factor β1（TGF-β1）. Methods：mHSC-T25 cell line was selected as experimental subject，and randomly divided into activation group（mH－SC-T25+10 ng/mL TGF-β1），inhibition group（mHSC-T25+l μmol/L TGF-β-R1 inhibitor） and control group（mHSC-T25）. mRNA expression of α-SMA，TGF-β1，TGF-β-R1，Jagged1，VEGF，HGF were detected by qRT-PCR. Expressions of α-SMA，Jagged1 were measured by immunocytochemistory. Protein expressions of TGF-β1，α-SMA，TGF-β-R1，Jagged1，Smad2/3，p-Smad2/3 were tested by Western blot. Results：①mRNA expressions of α-SMA，TGF-β1，TGF-β-R1，Jagged1，VEGF，HGF were significantly higher in ac－tivation group than in control group，but significantly lower in inhibition group. Activation group：（315.1±6.2）%，（524.8±14.3）%，（235.5±15.2）%，（548.7±16.6）%，（331.9±19.8）%，（376.00±6.51）%；inhibition group：（34.3±4.5）%，（29.0±10.7）%，（17.0±2.8）%，（17.4±4.7）%，（19.5±3.7）%，（16.2±2.7）%（P=0.000）. ②Expressions of α-SMA，Jagged1 were significantly higher in activation group than in control group and inhibition group. Activation group：0.880±0.016，0.796±0.015；control group：0.481±0.007，0.474±0.021；inhibition group：0.207±0.014，0.167±0.005（P=0.000）. ③Protein expressions of TGF-β1，α-SMA，TGF-β-R1，Jagged1，Smad2/3，p-Smad2/3 were significantly upregulated in activation group and significantly downregulated in inhi－bition group. Activation group：1.076±0.063，1.180±0.138，1.192±0.142，1.582±0.247，2.057±0.114，2.088±0.120；control group：0.689±0.022，0.654±0.061，0.710±0.380，0.817±0.116，1.203±0.105，1.168±0.107；inhibition group：0.374±0.011，0.359±0.012，0.378±0.069，0.364±0.059，0.664±0.063，0.573±0.120（P=0.000）. The results above showed that there was significantly statistical difference between three groups（P<0.05）. Conclusion：TGF-β1 activates mouse hepatic stellate cells and regulate their bio－logical activities via Jagged1/Notch.