Ground penetrating radar (GPR) is one of the most useful sensors for detection and identification of shallowly buried objects such as anti-personnel landmines in the ground [1]. However, for practical application of GPR systems to detect and identify shallowly buried objects, it is still insufficient for accurate detection and identification because of strong ground clutter. In order to use GPR systems successfully for target detection and identification, it is necessary to extract the target response accurately from measured GPR data. As an incident pulse, a simple shape waveform such as a monocycle pulse with a sharp peak and narrow width is convenient for time-domain analysis [2]. In actual measurement situation, however, the pulse waveform is distorted by characteristics of transmitting and receiving antennas when the pulse is radiated and received by the antenna pair. Therefore, a calibration that eliminates the antenna characteristics and makes the desired pulse waveform is important for accurate detection and identification. In our previous study [3][4], we proposed a method for calibration of the pulse waveform using a metal plate reflection as a reference data, and applied it to measured responses from objects in free space. In this study, we apply the method to responses from buried objects and demonstrate that the calibration of GPR responses is significant for reliable target response extraction [5]. © 2012 IEICE.