Abstract: The selection of string exerts great effect on gas well production. A reasonable string of production may increase throughput capacity, bleed liquid loading, thereby prolong the steady production capacity of liquid gas wells. This paper starts from the existing string selecting methods, proposes a method for selecting gas production string, i.e. selecting the rational inner diameter of tubing. The method is fulfilled by analyzing the string pressure loss, the critical liquid carrying flow rate, the erosion flow rate, and the sensibility with Hagedorn Brown model, Turner model, Beggs model, and node analysis separately. And finally the rational inner diameter of gas production string for liquid gas wells is determined.