We report a novel optofluidic resonance phenomenon in a liquid microjet triggered by non-coherent laser-induced fluorescence (LIF). By doping a $\sim$ 100 $\mu$m radius ethanol microjet with Rhodamine 6G dye and exciting it with a continuous-wave (CW) laser, the intrinsically random Rayleigh-Plateau instability is transformed into a highly ordered, satellite-free droplet generation process. We demonstrate that the jet effectively acts as a liquid optical fiber, trapping and transmitting the LIF emission upstream via total internal reflections. Such ordered jet breakup triggered by LIF is termed as optofluidic resonance. This resonating behavior is driven by a synergistic opto-thermal mechanism. The pulsating LIF exerts a localized optical radiation pressure combined with a temperature-dependent thermal Marangoni stress to seed periodic nanometer scale perturbations at the origin of the jet. These initial perturbations are subsequently amplified by macroscopic hydrodynamic instabilities. This work may provide a new non-contact way for precise microfluidic manipulation.