The energy and normal force of self-adatom on Pt(110) surface have been calculated by the modified analytical embedded atom method. The most stable position for a Pt adatom on Pt(110) surface is 0.11 nm above the hollow of the first layer atoms, and the best path for a Pt adatom migrating from a hollow to neighbor hollow is along the close-packed direction. On leaving the surface, the adatom will go through the repulsive, transitional and attractive regions, successively. In the repulsive and transitional regions, due to stronger pair interaction potential between adatom and the first layer atoms, the contour maps of the energy and normal force could be seen simply as a duplicate of the Pt(110) surface. This is consistent with the results of pair potential theory and embedded atom method. The complicated contour maps of the energy and normal force were obtained in the attractive region due to relatively increasing effects of the many-body interactions and nonspherical distribution of the electrons of the atoms in the crystal.