The aims of this sutdy was to investgate the action mechanism of polycation on the $eta$-glucan synthetase II (GS II) related to cell wall synthesis in suspension cultured carrot cells. In the suspension cultured cells treated with poly-L-Iysine($12{mu}M$) and poly-L-ornithine ($12{mu}M$) having ploycationic nature, GS II activity increased about 40% and 50% than that of the control respectively. And similar response was observed when ATP and NaF were treated. On the other hand, ploy-L-lysine and ploy-L-ornithine did nor affect the membrane permeability. Phorbol-12-myrlstate-13-acetate (TPA), activator of protein klnase, increased about 35% and 1-(5-isoquinolinyl sulfonyl)-2-methyl-piperrazine (H-7), inhibitor of protein kinase, decreased about 30% of GSII activity than that of control. These results suggest that polycation plays a role in the cell wall synthesis by increasing GS II activity through phosphorylation.