Provided is a radar device that can reduce the load of clustering processing and improve tracking performance. A tracking calculation unit (116) of a radar device (100) carries out clustering processing for grouping input measurement data groups into clusters, and tracking processing for smoothing the data and determining a prediction value for each cluster. In the radar device (100), cluster regions for dividing the measurement data into groups are fan-shaped. By using fan-shaped cluster regions and carrying out the clustering processing and tracking processing, the load of the clustering processing can be reduced and also the tracking performance can be improved.