A physical quantity measurement device includes a passage flow channel, a branch flow channel, and a physical quantity detection unit. An inflow region extending from the inflow port and a lateral region laterally arranged to the inflow region are included in at least one of the passage flow channel and the branch flow channel. The physical quantity detection unit is disposed in the lateral region. A guiding surface that guides away from the lateral region in the lateral direction foreign matter is included in at least one of an inner peripheral surface of the passage flow channel and an inner peripheral surface of the branch flow channel at a position upstream of the lateral region.
