A load detection sensor unit that is disposable below a seat cushion, the load detection sensor unit comprising: a load detection sensor that has a sensor sheet having a pair of resinous insulating sheets (56s, 57s), a first electrode provided on one of surfaces facing each other in the pair of insulating sheets (56s, 57s), and a second electrode disposed between the pair of insulating sheets (56s, 57s) and forming a pair with the first electrode, and a metal plate provided in at least a portion overlapping with the first electrode and the second electrode on one surface of the sensor sheet; and a pressing member that has a pressing portion (46, 146) disposed on the side of the metal plate opposite to the side of the sensor sheet and pressing the metal plate, wherein the pressing portion (46, 146) is harder than the seat cushion, the sensor sheet and the metal plate are bonded by an adhesive layer, further comprising a pedestal on which a block larger than at least the first electrode and the second electrode in the sensor sheet is disposed, and in the sensor sheet, a circumferential portion of at least a region overlapping with the first electrode and the second electrode in a pedestal facing surface to be a surface opposite to a surface to which the metal plate is attached and facing the pedestal is not adhered to the pedestal wherein: in the sensor sheet disposed on the pedestal, the region is adhered to the pedestal and the entire pedestal facing surface other than the region is not adhered. a load detection sensor that has a sensor sheet having a pair of resinous insulating sheets (56s, 57s), a first electrode provided on one of surfaces facing each other in the pair of insulating sheets (56s, 57s), and a second electrode disposed between the pair of insulating sheets (56s, 57s) and forming a pair with the first electrode, and a metal plate provided in at least a portion overlapping with the first electrode and the second electrode on one surface of the sensor sheet; and a pressing member that has a pressing portion (46, 146) disposed on the side of the metal plate opposite to the side of the sensor sheet and pressing the metal plate, wherein the pressing portion (46, 146) is harder than the seat cushion, the sensor sheet and the metal plate are bonded by an adhesive layer, further comprising a pedestal on which a block larger than at least the first electrode and the second electrode in the sensor sheet is disposed, and in the sensor sheet, a circumferential portion of at least a region overlapping with the first electrode and the second electrode in a pedestal facing surface to be a surface opposite to a surface to which the metal plate is attached and facing the pedestal is not adhered to the pedestal wherein: in the sensor sheet disposed on the pedestal, the region is adhered to the pedestal and the entire pedestal facing surface other than the region is not adhered. the pressing portion (46, 146) is harder than the seat cushion, the sensor sheet and the metal plate are bonded by an adhesive layer, further comprising a pedestal on which a block larger than at least the first electrode and the second electrode in the sensor sheet is disposed, and in the sensor sheet, a circumferential portion of at least a region overlapping with the first electrode and the second electrode in a pedestal facing surface to be a surface opposite to a surface to which the metal plate is attached and facing the pedestal is not adhered to the pedestal wherein: in the sensor sheet disposed on the pedestal, the region is adhered to the pedestal and the entire pedestal facing surface other than the region is not adhered.