Stochastic resonance (SR) is shown in a two-parameter system, a model of the photosensitive Belousov-Zhabotinsky reaction in a flow system. Light flux and a flow rate are control parameters in a newly developed Oregonator-type model, and the oscillatory behavior of the system is the dynamical observable. Modulation of an excitable focal steady-state close to a Hopf bifurcation by a periodic signal in one parameter and noise in the other parameter is found to give rise to SR. The scenario and novel aspects of SR in this system are discussed.