An analysis is developed for the calculation of creep deformation of an axisymmetric boilerrntube subjected to axisymmetric load. The stresses and the permanent strains at a particularrntime and at the steady state condition, resulting from loading of the tube under constantrninternal pressure and elevated temperature were evaluated when accounts is taken to thernsecondary creep characteristics of a given material. In this thesis first the formulation of anrnanalytical theory of creep for tubes according to the Bailey creep theory [41] was discussed.rnBailey theory was proposed for an idealized homogeneous material loaded uniaxially. Therntheory takes into account the initial elastic strain, the transient creep strain, and thernminimum creep rate strain. Next, more general solution by finite element method arernpresented and discussed for a class of problems in which no prior analytical solution mayrnexists; like the cases of cracked and/or pitted boiler tubes. The method of solution is anrnextension of the direct stiffness method. The body is replaced by a system of discreterntriangular cross-section ring elements interconnected along circumferential nodal circles.rnThe equations of equilibrium for the body are derived from the principle of minimumrnpotential energy. The creep behavior of the body is formulated in terms of creep laws inrncurrent use. Starting with the elastic solution of the problem, creep strains are treated asrninitial strains to determine the new stress distributions at the end of time interval. Thernprocedure is repeated until either the final time is reached or until the stress distribution isrnnot changed i.e. when a steady stated condition is reached. Calculated results according tornarbitrarily selected boiler tube data are shown at the end.