The 4,4'-diaminodiphenyl is introduced to prepare Poly(Ether-Block-Meta-Aramid), which rheological properties, thermal properties, fiber-forming properties and mechanical properties was studied.The result showed that Polymer belongs Non-Newtonian Fluid and 4,4'-diaminodiphenyl ether will slow the polymerization reaction rate;the decomposition temperature of the copolymer is 370℃ and without melting point;the Fiber forming ability will reduced as 4, 4'-diaminodiphenyl ether increased;the breaking strength and young's modulus of the fiber appeared a downward tendency as well as the elongation rose while the 4,4'-diaminodiphenyl content increased and fiber heat-resisting performance decreased.