[Caldas,M, "semi-T1/2-space" 1994] defined the concept of anew class of topological spaces called semi –T1/2 spaces. [ Kumar ,"Between semi closed set and semi-priclosed set" 1991] introduced a new class of spaces namely semi- T1/3 spaces he proved that the class of semi T1 spaces properly contains the class of semi-T1/2 spaces and he defined anew maps namely ?-continuity and he discuss the relation between this map and semi –continuity [Biswas,N "characterization of semi-continuous function",1970], g-continuity[Caldas,M,"on g-closed sets and g-continuous mapping" ,1993], [R.Devi, H.Maki and K.Balachandran,"semi-generalized closed map and generalized closed map" ,1993], [K.Balachandran ,P.Sundaram and H.Maki,"semi-generalized continuous maps and semi-T1/2", 1991], sg-continuity[P.sundaram, H.Maki, K. Balachandran,"on generalized continouos maps in topological spaces",1991], [P.Bhattacharya and B.K.Lahiri,"semi-generalized closed sets in topology" 1987] and gs-continuity[Miguel Caladas Cueva and Ratnesh Kumar saraf ,"A reaserch on charcterization of semi-T1/2-spaces " 2000]. The purpose of this paper that is give a new definition of these concepts in Bitopological spaces.