A clutter suppressing device (20, 40) for suppressing echo data of reflection waves caused by radar transmission signals reflecting on a static object, each of the radar transmission signals transmitted at a predetermined azimuth from a radar antenna at a predetermined time interval, the clutter suppressing device (20, 40) comprising: an echo data memory configured to sequentially store a plurality of echo data of reflection waves caused by the radar transmission signals reflecting on objects; a filter (21, 22) configured to select, from the plurality of echo data stored in the echo data memory, a data row in the azimuth direction for a predetermined distance, and suppress, in the data row, echo data of a target object moving at a speed within a predetermined range; and a suppression echo data output unit configured to output suppression echo data containing the echo data suppressed by the filter (21, 22); and wherein the predetermined range of the speed at which the target object moves includes zero speed; and wherein the filter (21, 22) includes: a suppression echo data memory configured to store the suppression echo data outputted from the suppression echo data output unit; a first weighting module configured to weight each data of the data row in the azimuth direction for the predetermined distance selected from the plurality of echo data stored in the echo data memory, and obtain a first sum value of the weighted data; a second weighting module configured to select, from the suppression echo data stored in the suppression echo data memory, a data row in the azimuth direction for the predetermined distance, weight each data of the data row, and obtain a second sum value of the weighted data; and a difference calculating module configured to obtain a difference between the first and second sum values, and cause the suppression echo data output unit to output the difference as the suppression echo data. an echo data memory configured to sequentially store a plurality of echo data of reflection waves caused by the radar transmission signals reflecting on objects; a filter (21, 22) configured to select, from the plurality of echo data stored in the echo data memory, a data row in the azimuth direction for a predetermined distance, and suppress, in the data row, echo data of a target object moving at a speed within a predetermined range; and a suppression echo data output unit configured to output suppression echo data containing the echo data suppressed by the filter (21, 22); and wherein the predetermined range of the speed at which the target object moves includes zero speed; and wherein the filter (21, 22) includes: a suppression echo data memory configured to store the suppression echo data outputted from the suppression echo data output unit; a first weighting module configured to weight each data of the data row in the azimuth direction for the predetermined distance selected from the plurality of echo data stored in the echo data memory, and obtain a first sum value of the weighted data; a second weighting module configured to select, from the suppression echo data stored in the suppression echo data memory, a data row in the azimuth direction for the predetermined distance, weight each data of the data row, and obtain a second sum value of the weighted data; and a difference calculating module configured to obtain a difference between the first and second sum values, and cause the suppression echo data output unit to output the difference as the suppression echo data. a suppression echo data memory configured to store the suppression echo data outputted from the suppression echo data output unit; a first weighting module configured to weight each data of the data row in the azimuth direction for the predetermined distance selected from the plurality of echo data stored in the echo data memory, and obtain a first sum value of the weighted data; a second weighting module configured to select, from the suppression echo data stored in the suppression echo data memory, a data row in the azimuth direction for the predetermined distance, weight each data of the data row, and obtain a second sum value of the weighted data; and a difference calculating module configured to obtain a difference between the first and second sum values, and cause the suppression echo data output unit to output the difference as the suppression echo data.