The aim of this paper is to provide a semantic criterion of the difference between indicative and subjunctive conditionals. The criterion is motivated mainly by Stalnaker’s explanation of the difference, which, however, is formulated outside semantics. The Stalnaker-Lewis “ontic” semantics for conditionals will be transformed into an epistemic framework which will enable us to view the difference as a semantic one. As a consequence, we will be able to say that indicative and subjunctive conditionals differ in their logics.