Abstract: The effect of Kappa--selenocarragreenan, an organic compound containing selenium, on aconitine, BaCl₂ and ouabain-induced arrhythmias were studied. When rats were given ip 9mg·kg^-1· d^-1×5 d or ig single dose of 35, 70, 140 mg. kg-~(1) the threshold dose of aconitine waselevated significantly to induce HA. The effect seems to resemble that of ip Na₂Se0₃1 mg·kg^-1·d^-4×5 d. With increasing ig dose, the threshold dose of aconitine was elevated for inducing VE, VT,VF. When ip 9 mg·kg^-1·d^-1×5 d or ig 70 mg·kg^-1 was given, the threshold doses of BaCl₂ in in-ducing VF(in rats) and ouabain in inducing VE(in guineapig) were elevated However. no influencewas observed for ip Na₂SeO₃ 1 mg·kg^-1 d^-1×5d.