An electromagnetic flowmeter is equipped with a pipe unit including a pipe through which a fluid to be measured flows, a pair of electrodes adhered to the pipe, and substrate holders that retain substrates therein and which are disposed so as to cover the electrodes. In addition, the pipe unit is accommodated inside a body through a first opening, which opens on one side of the body. A solenoid unit including coils is installed on the pipe unit after being inserted into the interior of the body through first and second openings.