Abstract： Objective To compare the positive rate of islet cell antibodies(ICA) between immunohistochemical and ELISA assays Methods The ICA assays were performed of 200 serum samples in the three different laboratories by three methods of two immunohistochemical assays with peroxidase labeled protein A (POPA) and avidin biotin complex (ABC), and ELISA method Results The positive and negative rates of ICA by POPA and ABC methods were consistent, but was significantly lower by ELISA than by POPA and ABC methods Conclusions The present results demonstrate that ICA assays with immunohistochemical POPA and ABC techniques are more veracious and reliable than with ELISA, suggesting POPA and ABC could be widely used in clinical practice