A pluripotent cell line, sea bream embryonic stem-like cells (SBES1), was developed from blastula-stage embryos of the cultured red sea bream, Chrysophrys major. The SBES1 cells were cultivated in Dulbecco's modified eagles medium (DMEM) medium supplemented with foetal bovine serum, marine fish serum, fish embryo extract, selenium, basic fibroblast growth factor and leukemia inhibitory factor. They were small and round or polygonal, and grew actively and stabely in culture. The cells exhibited a positive alkaline phosphatase activity upon histochemical staining. When the cells were treated with all-trans retinoic acid, they differentiated into various types including neuron-like, neuroglia-like and muscle-like cells, suggesting that the SBES1 cells remained pluripotent in culture. Chromosome analysis revealed that SBES1 cells had a normal diploid karyotype with 2n = 2st + 46t. At present, SBES1 cells have been cultured for >180 days with more than 60 passages. High survival rate has been obtained after cryopreservation of cell cultures. This embryonic cell line may potentially be used for the production of transgenic red sea bream.