The problem of elastic interaction between a surface step and an edge dislocation parallel to the surface is considered. Utilizing the displacement potential approach, the plane strain problem is solved analytically. A force on the edge dislocation due to step self-stress is evaluated as well as the one due to free surface. A potential minimum locus exists around the surface step for an edge dislocation. The relative configuration of step and dislocation (stepped direction and burgers vector direction) control the locus.