Abstract: Objective To observe morphological characteristics,immunophenotyping,differ-entiation and the expression level of epidermal growth factor (EGF)and transforming growth factor-β1 (TGF-β1)in skin mesenchymal stem cells (SMSCs)so as to explore the possible mechanism of psori-asis.Methods 35 patients with psoriasis and 35 patients with non-psoriasis were selected and de-signed as observation group and control group.SMSCs of 2 groups were separated and cultured.Immu-nophenotyping was determined by flow cytometry (FCM).Cell differentiation ability was evaluated by multidirectional differentiation method.The expression level of EGF and TGF-β1 was detected by ELISA.Results Morphological characteristics,immunophenotyping,differentiation of SMSCs were similar.The expression level of EGF in observation group was higher than control group (P <0.01), but the expression level of TGF-β1 was significantly lower than control group(P <0.01).In addition, the expression level of EGF and TGF-β1 in 2 groups had no significant relationship with the severity of disease(P >0.05).Conclusion The expression level of EGF and TGF-β1 is abnormal in patients with psoriasis,which may participates in the pathogenesis of psoriasis.