Abstract: Target positioning by airborne reconnaissance equipment is affected by many factors. The systematic errors and random errors in location data can affect the positioning results. We proposed that by using circular error probable(CEP) to process target location data, the different application conditions for CEP should be analyzed and judged. According to the definition of CEP and the general form of the CEP equation, we deduced the CEP simplified formulas under 6 different conditions and used two CEP simplified formulas to compare, calculate and analyze the location data of a target. Results show that the higher data processing accuracy 0.95 can be obtained using the formula under applicable condition, which meets the CEP-defined 50% probability data requirements and means the target location results from reconnaissance equipment can be analyzed accurately.