Abstract: Liquid-producing gas wells in Longfengshan Gas Field have reached a certain stage of production. Due to reduced pressure and production, those gas wells cannot meet the demand for liquid-carrying, forming bottom-hole fluid accumulation. What's worse, some wells with severe fluid accumulation have stopped production. The effect of trying foam drainage is not satisfactory. In order to find a new and more suitable drainage technology, Well Bei217 is preferred as the first plunger gas lift test well. The article elaborates the principle of plunger gas lift, summarizes the applicable conditions of the plunger gas lift drainage technology, and uses the applicable conditions to select a vertical well with liquid accumulation as a test well in Longfengshan. By comparing the production situation before and after applying the process, the effect and applicability of the plunger gas lift are analyzed. After the application of this technology in Well Bei217, the daily gas increases by 2000 m³. In the meantime, the efficiency of drainage is improved and the downhole fluid accumulation is reduced. Other gas wells in Longfengshan Gas Field can be tested in future. What's more, the downhole freeze blockage affects the plunger down, and alcohol injection is used to restore the plunger gas lift drainage.