  An equigenerated monomial ideal $I$ in the polynomial ring $R=k[z_1,\ldots,
z_n]$ is a Freiman ideal if $\mu(I^2)=\ell(I)\mu(I)-{\ell(I)\choose 2}$ where
$\ell(I)$ is the analytic spread of $I$ and $\mu(I)$ is the number of minimal
generators of $I$. In this paper we classify all simple connected unmixed
bipartite graphs whose cover ideals are Freiman ideals.
