Abstract: Underground pulse neutron oxygen activation flow measurement is specific logging equipment for actual well condi-tion repeatability and reproducibility during production logging procedure. There is no as yet reliable, accuracy and safety calibration methods at home and aboard at present. According to this situation, adopting oil-gas-water flow comprehensive investigate equipment combining with underground stimulation well to solve the actual flow calibration of this logging wells. Meanwhile, this method could conduct the calibration of underground flow testing equipment for conventional production measurement in oilfield, and be improved continuously during the application. At present, More than 200 sets of underground flow water-bearing test equipment and oxygen activation flow logging equipment were calibrated by this method, and the results prove that the method is safe, reliable and effective.