Fully protected 8‐D‐lysine‐vasopressin and 1‐deamino‐8‐D‐lysine‐vasopressin were synthesized by the solid phase method. Selective removal of the lysine protection and reaction with 1‐guanyl‐3,5‐dimethylpyrazole converted D‐lysine into D‐homoarginine. The title compounds were then obtained by treatment with sodium in liquid ammonia and oxidation in dilute aqueous solution. Although the antidiuretic activities are lower than for the corresponding D‐arginine derivatives, the even lower pressor effects make the new analogues highly specific antidiuretic agents. The A/P ratios for 8‐D‐homo‐arginine‐vasopressin and its 1‐deamino derivative are 100 and 3,300, respectively.