  The decay $K_S^0 \to \pi e \nu$ has been observed by the CMD-2 detector at
the e^+e^- collider VEPP-2M at Novosibirsk. Of 6 million produced $K_L^0K_S^0$
pairs, $75 \pm 13$ events of the $K_S^0 \to \pi e \nu$ decay were selected. The
corresponding branching ratio is $B(K_S^0 \to \pi e \nu)=(7.2 \pm
1.4)\times10^{-4}$. This result is consistent with the evaluation of $B(K_S^0
\to \pi e \nu)$ from the $K_L^0$ semileptonic rate and $K_S^0$ lifetime
assuming $\Delta S=\Delta Q$ .
