Abstract: The anti-pullout and anti-gluing are important indices for valuing the connection performance of API round tubing. Although satisfying applicable API specification, the tubing may still being operating with troubles like pullout and gluing. Finite element stress analysis is conducted in this paper under the conditions of make-up torque and axial tension load. The complications affecting the resistance against gluing and pullout of threaded connections are investigated, based on which, countermeasure are proposed. The said analysis conclusion may be used as a theoretical guide to enhancing API tubing performance.