In the method for determining a relative position of a mobile unit by comparing scans of an environment, scans of an environment of the mobile unit are recorded continuously by a distance sensor and stored in a memory. Furthermore the processing unit compares a first scan with a second scan, with a relative position of the mobile unit at the time of the second scan being determined in relation to a position at the time of the first scan. The method is characterized by the fact that the processing unit compares the first scan iteratively with subsequent scans, with a new relative position of the mobile unit at the time of the relevant subsequent scan being determined relative to the position at the time of the first scan, and with the last relative position determined in each case being taken into account as a-priori information.