The all para polyether ketone ketone (PEKK) whic possesses good mechanical properties was synthesized by the high temperature condensation reaction between 1,4-bis (4’-hydroxybenzoyl) benzene and 1,4-bis(4’-fluorobenzoyl) benzene,the general properties of PEKK were characterized by DSC,IR,TGA,WAXD and Mechanical Properties Measurement.The results indicate that the melting temperature of PEKK is 50℃ higher than that of PEEK and still keep the high temperature resistant property of PEEK,the crystallization structure of PEKK still assigns to orthorhombic system.When amorphous PEKK was annealed below 230℃,the glass transition temperature increase with the increasing of the heat treatment temperature,while above 230℃,the glass transition temperature keep a constant,the low melting peaks linearly increase when annealing temperature are increased,the high melting peaks keep a constant regardless of the heat treatment temperature.The crystal structure of the slow-cooling crystallization specimens have a distinction with that of heat treatment crystallization samples.