Aim To investigate the effects of noradrenalin on the expressions of transforming growth factor(TGF-)β1 in human THP-1 macrophage cells.Methods THP-1 macrophage cells were incubated with different concentrations of noradrenalin(10 pmol/L ～10 μmol/L)for 24 hour.Then the mRNA levels of TGF-?1 were determined by reverse transcription polymerase chain reaction(RT-PCR).Levels of TGF-β1 in the supernatants of cells were determined by enzyme-linked immunosorbent assay(ELISA).Results THP-1 macrophage cells which treated with 100 nmol/L,1 μmol/L and 10 μmol/L noradrenalin,the mRNA levels of TGF-β1 decreased 9.3%(p<0.05),39.5%(p<0.01)and 47.8%(p<0.01)respectively.THP-1 macrophage cells which treated with 1 μmol/L and 10 μmol/L noradrenalin,the protein levels of TGF-β1 decreased 24.7%(p<0.01)and 32.8%(p<0.01)respectively.Conclusion Stress induced increase of noradrenalin concentrations cause TGF-β1 expression decreased in human THP-1 macrophage cells.