A multi-operation laser oscillator is developed and built with multiple operation modes (OMs): injectionseeding mode, cavity-dumping mode and Q-switching mode.With the same electrical energy pumping, the multioperation laser oscillator provides different output energies and pulse durations for different OMs. In the Q-switching mode, the output coupling is optimized for different electrical energy pumping. The laser oscillator operation can be switched between different modes conveniently. The multi-operation laser sources could be operated in multiple OMs for various research and application requirements.