Abstract: OBJECTIVE To discuss humoral immune function in hand foot and mouth disease children and its relationship with the degree of the disease, so as to provide references for clinical treatment of hand foot and mouth disease. METHODS Clinical data of 214 cases of children with hand foot and mouth diseases diagnosed and treated from Aug. 2014 to Aug. 2015 were collected, and their humoral immunity was detected. The results were statistically analyzed by software SPSS219.0. RESULTS The IgA, IgG, IgM, C3 and C4 of children with different sexes and different ages had no significant differences. IgM in severe sickened children and children with complications were (1.89±0.44)g/L and (1.92±0.53)g/L, in mild sickened children was (1.67±0.27)g/L, there was significant difference in the comparative differences between severe sickened children with complications and mild sickened children without complications (P<0.05). CONCLUSION Children with hand foot and mouth disease always have humoral immune function disorder, the main performance is the increase of IgA, while IgM and IgG decrease. When the condition is serious, and with encephalitis and pulmonary edema, the above situation that body fluid immune disorders significantly increase.