During the mapping task using high-resolution airborne SAR images, the effective using of DGPS data has important influence on the final accuracy and efficiency of surveying and mapping. This paper analyzed the imaging geometric characteristics of airborne SAR system, and, under the condition of space-constant PRF imaging technique, it put forward to a kind of flight track processing method for radar sensor position correction using iteration computation supported by DGPS data. And further, it discussed the data processing flow for direct geo-location application from airborne SAR images, and utilized the test dataset in Sichan area in China to testify the relative methods. The test results showed that the methods are reliable and effective, and it can improve the research on direct geo-location from airborne SAR images as a reference method.