OBJECTIVE: To investigate the association of the polymorphism of I181L, V183L and E237G in the high affinity immunoglobulin E receptor β-chain (FcεR1β) with the susceptibility of childhood asthma and the serum total immunoglobulin E(IgE) level. METHODS: The coding variants of I181L, V183L and E237G and the serum total IgE level were detected using amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and double antibody sandwich ELISA respectively in 50 asthmatic children and 40 normal controls from Sichuan Province. The association of gene mutation with the susceptibility of asthma and the serum total IgE level was analyzed. RESULTS: There were 5 cases of I181L mutation, 2 of V183L mutation, and 7 of E237G mutation in the Asthmatic group. There was no mutation in the Normal control group. The frequency of I181L and E237G mutation in the Asthmatic group were statistically higher than in the Normal control group (P<0.01). The serum total IgE level in the Asthmatic subgroup with I181L mutation (2.837±0.407) or E237G mutation (3.044±0.419) was significantly higher than in the Asthmatic subgroup without gene mutation (2.156±0.638) and the Normal control group (1.348±1.291) (P<0.05 or 0.01). CONCLUSIONS: The polymorphism of FcεR1βI181L and E237G is a susceptible gene of childhood asthma and closely associates with the increased serum total IgE level.