In this paper, the quadratic and cubic spline local interpolations on a sectorial elemeat in polar coordinates is discussed and a class of spline sectorial elements for analyses of plane and thin plate problems are presented. A reasonable treatment of the assumed displacement fields for elements with nodes at the origin(r=0) is made so that the elemeats can not only characterize the geometrical properties at the origin but also remove the siagularitp of strains and stresses there.Some numerical examples are given to show the efficiency of the proposed elemeats.