Provided is a magnetic sensor device, which is configured to connect each terminal of a Hall element to another end of a variable resistor having one end connected to GND by switching of four switches. Thus, a detection voltage level for a magnetic field intensity can be arbitrarily set with a small-scale circuit. The detection voltage level is determined only by the resistance ratio, and hence the influence of fluctuations in power supply voltage and manufacturing fluctuations can be suppressed. This configuration can simplify signal processing and achieve higher-speed signal processing.