To provide a novel two-wire type electromagnetic flowmeter so that the flowmeter can have the same performance as that a four-wire type flowmeter does by providing a period during which excitation is intermittently ceased and synchronizing the signal transmitting timing with the excitation ceasing period.

A sequence means composed of software is provided to an arithmetic and control circuit 24 so as to output a digital pulse signal P1 except a current fluctuating period (exciting period). Since the circuit 24 controls the timing of all components of a converter 2, such as an excitation circuit 21, a communication circuit 25, etc., communication can be made except an exciting period in which current ripples are generated when the software sequence in an arithmetic and control circuit 23 is modified. Since the power consumption is small and stable during an excitation ceasing period, high-S/N communication can be executed when the communication is executed during this period only. When a power unit 3 also monitors the supplied current, the excitation ceasing period of the converter 2 can be discriminated easily and the communication to the converter 2 from the unit 3 can be performed.