This paper briefly describes the working principle of the self-excited oscillating nozzle and the experimental results of the pressure impulse characteristics and its frequency distribution under different ambient pressures. The transmitting law of the pressure fluctuation is introduced along the casing in both the axial and the radial directions. In addition, it presents the principle of water-injection with self-excited oscillation, the designation of the injection tool, and the field experimentation results. The field results indicate that the self-excited oscillating cavitation jets can be used as an effective way to prolong the production period of the well because the jets minimize formation block up. The average injection pressure was reduced by 2.1MPa, and the averaged volume of daily water injection for a single layer increased by 29m3. It can also prolong the water injecting time of the general waterinjecting well