An optofluidic switch based on microfluidic bistable oscillator was designed, which is conducive to keep up with the trends of integration, miniaturization and low power consumption. The insertion loss of the two optical outputs are 1.03 dB and 0.18dB, respectively. Microfluidic bistable oscillator consists of two symmetrical cascaded normally closed micro-valves, the optical switch is made up of three embedded optical fiber waveguides in the oscillator output part. A micro-syringe pump is used to drive the liquid and finally control the states of the switch. The impact factors of switching cycles were studied by using simulation software. The results show that when the injecting flow rate changes from 0.2 mm/s to 1.0 mm/s, the switching cycle is reduced from 1.25 s to 0.26 s. Simultaneously, the duty cycle is approximately 0.5 owing to the symmetrical design. The threshold of valve is providing the linear relationship with the switching time constants. With the widening of the normally closed valve seat, switching cycle is increased; with the decrease of valve aspect ratio, switching cycle is reduced. Moreover, asymmetrical design of the valves can adjust the duty cycle of the micro-oscillator. By adjusting the threshold characteristic of the valve and changing the inlet flow rate, an optical switch with specific frequency as need can be designed.