In a marker detection method for detecting magnetic markers (10) laid in a road by sensor units (11) attached to a vehicle (5), in a marker detection system (1) including two sensor units (11) arranged so as to be separated in a longitudinal direction of the vehicle (5) and two magnetic markers (10) arranged at spacings equal thereto so as to be simultaneously detectable by the two sensor units (11), magnetism generation sources simultaneously detected by the two sensor units (11) are detected as the magnetic markers (10), thereby reducing erroneous detection.