The author studied 32 cases of macroamylasemia. IgA was the most common in amylase binding substances. During the follow up period of 1 month to 3 years and 4 months, small flactuations of serum amylase values were seen in many cases. Cases classified in Berk 2 type were most frequently seen. In the amylase isozyme analysis by electrophoresis, the band of IgA binding substance appeared at S-amylase position and IgG binding substance appeared at P-amylase position.