A fluid measurement device includes a circuit unit into which a first signal output from a first detection element and a second signal output from a second detection element are input. The circuit unit includes a signal processing part, a state deciding part, and a controller. The controller controls an amount of change that a change of the first signal imparts to the third signal in accordance with a result of decision by the state deciding part that determines that the state of the first signal is not within the predetermined range. The predetermined range is based on the second signal.