The article is devoted to isomorphisms of probabilistic metric spaces. Two theorems are proved: Theorem 1. If a probabilistic metric space \((E,F)\) is isometrically isomorphic to a generating space of a quasi-metric family, then there is a probabilistic metric space \((E',F')\) such tha t\((E,F)\) is isometrically isomorphic to \((E',F')\). Theorem 2. If a probabilistic metric space \((E,F)\) is isometrically isomorphic to another probabilistic metric space \((E',F')\) with \(\sup\{\widetilde T(a,a): a< 1\}= L\), where \(\widetilde T\) denotes the best weak \(t\)-norm of \((E',F')\), then there is a generating space of quasi-metric family \((E',d_r,r\in(0,1))\) such that the probabilistic metric space \((E,F)\) is isometrically isomorphic to the generating space of the quasi-metric family \((E',dr,r\in (0,1))\).