The effect of some chemotherapeutic (Praziquantel,Levimasol,chloroquinephosphate,Trimethoprim-Sulphamethoxazol and Clindamycine ) on the course of choronic toxoplasmosis in experimentally infected rats was studied .Obtained data showed that,praziquantel ,levimasol and chloroquine phosphate had no therapeutic effect on choronic toxoplasmosis in rats , while trimethoprime-sulphamethoxazol and clindamycine hydrate exerts some therapeutic effects on choronic toxoplasmosis