Abstract: Take 89mm wire-line drill pipe as the research object, a quasi three dimensional model of the threaded connec-tion part is established, with the analysis on the contact nonlinear mechanics by using CAE finite element software ANSYS, the equivalent stress and deformation nephogram at the threaded connection of drill pipe are obtained.The results show that the maximum equivalent stress position and deformation state is exactly consistent with the common position and the state of the drill pipe fracture in the drilling field, which shows that the above research means and methods presented in this paper are feasible.