For a polynomial $p$ on $\mathbf{C}^{n}$ , the variety $ V_{p} = \{ z \in \mathbf{C}^{n} ; p(z)=0 \} $ will be considered. Let $\mathrm{Exp}(V_{p})$ be the space of entire functions of exponential type on $V_{p}$ , and $\mathrm{Exp}^{\prime}(V_{p})$ its dual space. We denote by $\partial p$ the differential operator obtained by replacing each variable $z_{j}$ with $\partial / \partial z_{j}$ in $p$ , and by $\mathcal{O}_{\partial p}(\mathbf{C}^{n})$ the space of holomorphic solutions with respect to $\partial p$ . When $p$ is a reduced polynomial, we shall prove that the Fourier-Borel transformation yields a topological linear isomorphism: $\mathrm{Exp}^{\prime}(V_{p}) \to \mathcal{O}_{\partial p}(\mathbf{C}^{n})$ . The result has been shown by Morimoto, Wada and Fujita only for the case $p(z) = z_{1}^{2} + \cdots + z_{n}^{2} + \lambda \, (n \geq 2)$ .