A semiconductor device comprising: a substrate; a first main MOSFET (Metal Oxide Semiconductor Field Effect Transistor) that includes a first source electrode formed on the main surface side of the substrate and a first drain electrode formed on the back surface side of the substrate; a second main MOSFET that has a second source electrode formed on the main surface side of the substrate and shares the first drain electrode with the first main MOSFET; a first sense MOSFET that includes a first sense electrode formed on the main surface side of the substrate and a second drain electrode formed on the back surface side of the substrate and detects a main current flowing in the first main MOSFET; a second sense MOSFET that has a second sense electrode formed on the main surface side of the substrate, shares the second drain electrode with the first sense MOSFET, and detects a main current flowing in the second main MOSFET; a first gate pad that is electrically coupled to a gate electrode of the first main MOSFET and a gate electrode of the first sense MOSFET and is formed on the main surface side of the substrate, and a second gate pad that is electrically coupled to a gate electrode of the second main MOSFET and a gate electrode of the second sense MOSFET and is formed on the main surface side of the substrate, wherein the first drain electrode and the second drain electrode are configured using a common metal layer, and wherein each of the shortest distance between a source diffusion layer of the first sense MOSFET and a source diffusion layer of the second main MOSFET and the shortest distance between a source diffusion layer of the second sense MOSFET and a source diffusion layer of the first main MOSFET is at least three times the shortest distance between the source diffusion layer of the first sense MOSFET and the source diffusion layer of the second sense MOSFET. a substrate; a first main MOSFET (Metal Oxide Semiconductor Field Effect Transistor) that includes a first source electrode formed on the main surface side of the substrate and a first drain electrode formed on the back surface side of the substrate; a second main MOSFET that has a second source electrode formed on the main surface side of the substrate and shares the first drain electrode with the first main MOSFET; a first sense MOSFET that includes a first sense electrode formed on the main surface side of the substrate and a second drain electrode formed on the back surface side of the substrate and detects a main current flowing in the first main MOSFET; a second sense MOSFET that has a second sense electrode formed on the main surface side of the substrate, shares the second drain electrode with the first sense MOSFET, and detects a main current flowing in the second main MOSFET; a first gate pad that is electrically coupled to a gate electrode of the first main MOSFET and a gate electrode of the first sense MOSFET and is formed on the main surface side of the substrate, and a second gate pad that is electrically coupled to a gate electrode of the second main MOSFET and a gate electrode of the second sense MOSFET and is formed on the main surface side of the substrate, wherein the first drain electrode and the second drain electrode are configured using a common metal layer, and wherein each of the shortest distance between a source diffusion layer of the first sense MOSFET and a source diffusion layer of the second main MOSFET and the shortest distance between a source diffusion layer of the second sense MOSFET and a source diffusion layer of the first main MOSFET is at least three times the shortest distance between the source diffusion layer of the first sense MOSFET and the source diffusion layer of the second sense MOSFET.