Objective In order to investigate the relationship between erythrocyte immune function and selenium(Se) level.Method Red blood cell immune adherence(RCIA) function,serum RCIA regulatory factor, blood Se content and activities of glutathione peroxidase(GPX) of residents in Keshan disease(KD) endemic and non endemic areas were comparatively studied.Forty eight residents in KD endemic area aged 13~16 years were divided into 2 groups.The residents in the experimental group were orally given 200μg Se daily as Se yeast for 12 weeks, and their erythrocyte Se content and activity of glutathione peroxidase (GPX),RCIA function,serum RCIA regulatory function and circulating immune complexes(CIC) content were determined.Results The results showed that the rosette formation rates of erythrocyte C 3b R and blood Se levels of the residents in KD area were significantly lower and the rosette formation inhibitory rate of serum RCIA of the residents in KD area was significantly higher than those in the non endemic area.Erythrocyte Se contents, GPX activities and rosette formation rates of erythrocyte C 3b R were significantly increased and the rosette formation inhibitory rates of serum RICA were significantly decreased after supplementing Se,but the difference in the contents of serum CIC was not significant.Conclusion The increase of erythrocyte immune function by Se supplement might be one of the effective mechanisms in the prevention of KD by Se supplement. Objective In order to investigate the relationship between erythrocyte immune function and selenium (Se) level. Meth Red Blood cell immune adherence (RCIA) function, serum RCIA regulatory factor, blood Se content and activities of glutathione peroxidase (GPX) of residents in Keshan disease (KD) endemic and non endemic areas were comparatively studied. Forty eight residents in KD endemic area aged 13 to 16 years were divided into 2 groups. The residents in the experimental group were orally given 200 μg Se daily as Se yeast for 12 weeks, and Their erythrocyte Se content and activity of glutathione peroxidase (GPX), RCIA function, serum RCIA regulatory function and circulating immune complexes (CIC) content were determined. Results showed that the rosette formation rates of erythrocytes C 3b R and blood Se levels of the residents in KD area were significantly lower and the rosette formation inhibitory rate of serum RCIA of the residents in KD area was significantly higher than those in the non endemic area. Erythrocyte Se contents, GPX activities and rosette formation rates of erythrocyte C 3b R were significantly increased and the rosette formation inhibitory rates of serum RICA were significantly decreased after supplementing Se, but the difference in the contents of serum CIC was not significant. Confound The increase of erythrocyte immune function by Se supplement might be one of the effective mechanisms in the prevention of KD by Se supplement.