The semibending theories of thin walled cylindrical shell construction neglect the increment in curvature of the shell in the axial direction. The basic differential equations of the shells using the semibending theories are derived for three different cases and are named as simpli-fied semibending, semibending theory with incompressible middle surface and semibending theory with compressible middle surface. The differen-ces between these theories depend on the values of the circumferential normal strain and the shear strain. The derived differential equations are solved and applied to the prnblems of influence lines of stresses and deformations for different loading conditions on a long shells.