We are concerned with the following nonlinear Schrodinger equation $$-varepsilon^2Delta u+ V(x)u=|u|^{p-2}u,~uin H^1(R^N),$$ where $Ngeq 3$, $2<p<frac{2N}{N-2}$. For $varepsilon$ small enough and a class of $V(x)$, we show the uniqueness of positive multi-bump solutions concentrating at $k$ different critical points of $V(x)$ under certain assumptions on asymptotic behavior of $V(x)$ and its first derivatives near those points. The degeneracy of critical points is allowed in this paper.