Because of the developmental progress of western ethnic areas, there are realistic soil restricting the legal construction of national unification. Except for the lagged some problems in the economic development, there are two kinds of ＂rule of man＂ cultural soil which are interweaved with each other, and they are slavery and feudalism. Then, it became the broadly traditional ＂man of rule＂ soil. Meanwhile, the accustomed legal soil has a great impact on the legal construction of national unification from the narrow tradition perspective. These different kinds of soil mixed together, presenting a complicated pattern, which restricted the legal construction of national unification in western ethnic areas.