Orthogonal meshless method is based on an improved mobile least-squares approximation, IMLS approximate calculation of approximate have higher accuracy and efficiency than MLS, the system equation won't produce pathological; When structural orthogonal basis shape function derivative need to undertake trivial derived. The local orthogonal basis function has the same attributes as the primitive orthogonal basis function; its derivatives have much simpler expressions, higher efficiency. And it apply to electromagnetic field, the discrete model is established. Through numerical column proves the method feasibility and effectiveness.