A dual-mode 3 dB power splitter for application in an on-chip mode (de)multiplexing system is proposed and demonstrated. This device is composed of mode converters cascaded with a Y-junction. The simulation results show that ∼50∶50 splitting ratio can be achieved for both TM0 mode and TM1 mode over a wide wavelength range from 1.52 to 1.62 μm. The fabricated device, which consists of a multiplexer, a dual-mode 3 dB power splitter, and a demultiplexer, has insertion losses of 0.54 dB for TM0 mode and 0.86 dB for TM1 mode at 1.55 μm wavelength. The measured cross talk is 15.7 and 17.2 dB at 1.55 μm wavelength for the TM0 mode and TM1 mode, respectively.