In order to study the feasibility of piggyBac transposon application in the fish, the plasmid consisting of the piggyBac inverted terminal repeats flanking a fusion of the Bombyx mori cytoplasmic actin gene BmA3 promoter and the enhanced green fluorescent protein (EGFP) gene and a nonautonomous helper plasmid encoding the piggyBac transposes was introduced into the zygote of the Macropodus opercularis through microinjection. The PCR identification indicated that the EGFP gene mediated by piggyBac transposon existed in the genome of the M. opercularis. Transgene was stably transferred to the next generation through normal Mendelian inheritance. The foreign DNA integration rate, i.e., the rate of number of G1 broods with EGFP positive fish to the number of fertile fish was 12.30%. These results prove that piggyBac plasmid can be a new vector for the transgenic experiment in fish. The system constructed in our experiment is feasible.