In　the　complex　conversion　analysis　of　multi-degree-of-freedom　system,　there　are　large　calculation　counts　in　every　calculation　step　of　genetic　algorithm,　which　limit　the　running　speed　of　genetic　algorithm.　So　the　positive　calculation　counts　to　be　reduced　is　an　effective　method　to　enlarge　the　range　of　genetic　algorithm　application.　The　empirical　genetic-simplex　algorithm　is　one　of　the　effective　method　to　solve　the　problem.　In　this　paper,　the　empirical　genetic-simplex　algorithm　is　applied　to　structural　physical　parameter　identification　based　on　incomplete　modal　parameters.　The　results　show　that　the　empirical　genetic-simplex　algorithm　has　many　advantages,　such　as　high　precision　and　searching　efficiency,　independence　of　the　selection　of　initial　values,　and　sufficient　reflection　on　the　inadequate　high　rank　modal　information.