Constraints from $b \to s \gamma$ on gauge-mediated supersymmetry breaking models

We consider the branching ratio of $b \to s\gamma$ in gauge mediated supersymmetry breaking theories. Useful bounds on the parameter space of these models are derived from the experimental bounds on $b \to s\gamma$. Constraints on masses of NLSP are presented as a function of $tan\beta$ and $M/\Lambda$ for $\mu<0$ and $\mu>0$.