Abstract： Objective In order to provide reference for clinic,this paper reports a rare heterozygote Hb Lepore-Boston-Washington(Hb LBW)in China and pay attention to detail(inspection of the capillary zone electrophoresis system and HPLC chromatogram in this case)and awareness of strengths and pitfalls of each screening technique.Hematological characteristics and clinical phenotype were discussed and compared with cases in previous literatures.Methods Peripheral blood was collected for hematological analysis.Three common deletion α-thalassaemia(-α3 7,-α4,2,--SEA),three common non-deletion a-thalassaemia(Hb Constant Spring,Hb QuongSze and Hb Westmead)and 17 common mutations were analyzed by PCR-flow fluorescence hybridization,and DNA sequencing was used to analyzed β-globin gene.Results His haematology profile showed a Hb of level 136 g/L,RBC:5.8× 1012/L,MCV:71.4 fl and MCH:23.4 pg.On the capillary zone electrophoresis,the results of Hb typing showed that the contents of Hb A,Hb A2,Hb F and Hb D were 84.7％,2.3％,2.9％and 10.1％,respectively.DNA analysis revealed the patient was a rare heterozygote Hb Lepore-Boston-Washington carrier.Conclusion This rare Hb LBW mutation in the Chinese population could explain variant Hb peak and raised Hb F level resulting from unequal crossover events occur between the homologous regions of the δ-codon 88 to β-IVS-Ⅱ nt 8 that would form a fusion gene.An accurate diagnosis could be reached with the help of DNA analysis.In areas where thalassemia has a relatively high prevalence in southern Chinese population,extreme attention is necessary for couples who seek for preconception genetic consultation,especially when one partner has been identified to have β-thal trait.