Let $q(x)$ be real-valued compactly supported sufficiently smooth function,$q\in H^\ell_0(B_a)$, $B_a:=\{x: |x|\leq a, x\in R^3$ . It is proved that thescattering data $A(-\beta,\beta,k)$ $\forall \beta\in S^2$, $\forall k>0$determine $q$ uniquely. here $A(\beta,\alpha,k)$ is the scattering amplitude,corresponding to the potential $q$.
