In this paper, the concept of a pseudosymmetric space which is a natural generalization of the concept of a symmetric space is defined. All basic concepts such as the Luxemburg representation theorem, the Boyd indices, the fundamental function and its properties, Calderon’, s theorem, etc., is transferred over the pseudosymmetric case. Examples are given for pseudosymmetric SPACES. The quasi-symmetric SPACES expand the scope of the application of symmetric space results.