We propose an efficient multiplexed sensing system for detecting bladder cancer biomarkers without invasiveness, labeling, and high cost using a silicon-based dual microring resonator biosensor. The dual microring biosensor consists of a sensing microring and an electrical tracing microring. The working principle of the sensor is that a resonance wavelength shift of sensing ring is induced by the refractive index change resulted from biomarker binding to the ligand on the sensing microring. Then, the shift is traced and determined by the tracing ring through direct voltage supply. Also, we have shown the specific detection of HER-2 protein which is known as one of bladder cancer biomarker using the dual microring sensor.