Abstract: Gas circle drilling is a new drilling technology, which is difference from conventional gas drilling. When gas drilling is transformed into the cyclic form, the pressure and gas velocity in the bore hole will be changed, as a result the carring capacity of the rock will be influenced. So it is of great significance to carry out simulation research on the gas circle drilling in the lab. Based on the similarity theory, taking the pressure variation regulalarity as the research target, three simulation methods of gas circle drilling are studied in the lab, i.e. the similar dynamic simulation that is applicable to the simulation of key points, the similar Reynold’s mumber simulation that is applicable to the simulation of the whole process, and the similar Euler number simulation that is applicable to the simulation of some hole sections. They are proved to be feasible as the results of the related simulation coincide with the theory, providing theoretical basis for the lab simulation of gas circle drilling.