The author studied the adrenotropic receptors of isolated vas deferens from Ditrema temmincki Bleeker, using adrenergic activators such as epinephrine, norepinephrine, isoproterenol and phenylephrine, and adrenergic blocking agents such as phenoxybenzamine and propranolol. The results are as follows: 1. The vas deferens was stimulated by epinephrine, norepinephrine and phenylephrine, but not affected by isoproterenol. 2. The excitatory effect of phenylephrine on the vas deferens was completely blocked by phenoxybenzamine, but more stimulated by propranolol. 3. The excitatory effects of epinephrine and norepinephrine were markedly reduced by phenoxybenzamine, but stimulated by propranolol. 4. The vas deferens pretreated with phenoxybenzamine and propranolol was not affected by epinephrine and norepinephrine. 5. The vas deferens was not affected by isoproterenol and also not affected by the pretreatment with either kind of blocking agent plus isoproterenol. 6. It seemed that the vas deferens had both alpha-excitatory receptor and beta-receptor, but it was difficult to detect the character of beta-receptor whether it was inhibitory or excitatory.