This study was conducted to investigate the effects of urotensin-II (UII) on the proliferation of pheochromocytoma cells and the mRNA expression of UII and its receptor G protein-coupled receptor 14 (GPR14) in normal adrenal and human pheochromocytoma tissues. The effects on the cell proliferation by different UII concentrations and at different time were observed with the MTT method in both rat pheochromocytoma cell line (PC12 cell) and human pheochromocytoma cells. The mRNA expression of UII and GPR14 was evaluated by RT-PCR. UII had no significant effect on the proliferation in PC12 cells, but promoted the proliferation of human pheochromocytoma cells. The mRNA expression of UII and GPR14 in pheochromocytoma was lower than that in normal adrenal tissues. But mRNA expression of UII and GPR14 in adrenal pheochromocytomas was lower than that in extra-adrenal pheochromocytomas. Thus, UII and its receptor GPR14 exert a possible effect in the pathogenesis of pheochromocytoma.