A magnetic sensor circuit includes: a Hall element; a comparator circuit for comparing a Hall voltage corresponding to a magnetic flux passing through the Hall element with a threshold voltage; an output logic determination circuit for determining output logic of the magnetic sensor circuit based on an output signal from the comparator circuit; a threshold voltage control circuit for determining the threshold voltage based on a data signal output from the output logic determination circuit; and a threshold voltage output circuit for outputting the threshold voltage for the comparator circuit based on a data signal output from the threshold voltage control circuit. Therefore, the magnetic sensor circuit in which a circuit scale is small, and increase in current consumption and cost is suppressed can be provided.