Abstract: Yaha condensate gas field features in high content of condensate oil,deep wells,high temperature,and high salinity of water quality,so common foaming agents does not work at all.In view of this,research on the technology of gas recovery by foam drainage for condensate gas wells featuring in big depth,high temperature,and high salinity is put forward in this paper.Experiment of gas recovery by foam drainage is conducted in Well Yaha-501 where water accumulation is serious.By simulating the downhole temperature,laboratory evaluation is made on three types of foaming agents and the liquids produced from Well Yaha-501.As a result,UT-11C foaming agent is selected based on taking the capacity to carry liquid as the main index.The technical index of the foaming agent is excellent and is suitable for the conditions of Yaha condensate gas field which features in deep wells,high temperature,and high salinity.The capacity of UT-11C foaming agent to carry liquid is the best when its volume concentration is 0.5% based on experiments.After five months of field experiment,the technology of gas recovery by foam drainage turns out to be successful.It will be one of the major measures to guarantee the later stable production of Yaha condensate gas field for its low investment,fast effect,low risk,and high benefit.