A magnetic resonance multi-core array radio frequency device and a magnetic resonance signal receiving method are provided. The device comprises a radio frequency receiver which includes a radio frequency coil (11), a low noise preamplifier (13), a multiplexer (15), a radio frequency band-pass filter (17), a program control amplifier (19), a frequency synthesizer (21), a mixer (23), an analog to digital converter (29) and a controller (31). The controller (31) is used for controlling the multiplexer (15) to select a corresponding radio frequency coil channel, a corresponding filtering channel, gain of the radio frequency band-pass filter (17), and receiving a magnetic resonance digital signal transmitted by the analog to digital converter (29). Due to the multiplexer (15), there is no need to configure different circuits respectively for different nuclear magnetic resonance, redundancy of the circuits is reduced, and cost is reduced.