Abstract: Synthetic aperture ladar(SAL) has the potential to image long distance objects with high resolutions. However, due to the short laser wavelength used, tiny mechanical vibrations in the SAL system will possibly course enormous phase errors in the target backscattered signals. As a result, it is difficult to obtain stable phase history data in SAL and high resolution SAL images are usually formed by additional phase error removing techniques, especially phase gradient autofocus(PGA) technique. In this paper, a well-performed stripmap mode SAL is demonstrated in the laboratory. Using a linearly wavelength scanning laser in the 1 550 nm range as the detecting source, the SAL can generate well-focused high resolution images. By carefully designing the system, most mechanical vibrations that will introduce phase errors into the backscattered signals are suppressed. The phase history data generated in the SAL are so stable that high resolution images are formed by straightforwardly following the standard SAL image formation theory and not relying on PGA. Using dot target calibration, both the azimuth and range resolutions of the SAL are measured to near its theoretical estimations. At target distance of 2.4 m, well focused SAL images with various targets, together with their stable phase history data, are illustrated in detail.