Copolyamides based on polyisophthalamide, to which 2,2'-bibenzoyl chloride(2,2'-BC) moieties were inserted, were synthesized. The copolymer obtained by condensation of m-phenylene containing diamines such as isophthaloyl chloride(IPC), 3,4'-oxydianiline, and 1,3'-bis(4-aminophenoxy)benzene, with the mixed diacid chlorides of IPC and 2,2'-BC. The resultant copolymers had inherent viscosities in the range of 0.32 ~ 0.68 dL/g and showed amorphous patterns in X-ray diffraction studies. Most of copolymers exhibited excellent solubility and could be readily dissolved in various solvents such as NMP, DMAc, DMF, DMSO, pyridine, m-cresol, and cyclohexanone. These copolymers had glass transition temperatures between 213 and 265 ℃ and 10% weight loss temperature in air and nitrogen were in the range of 416 ~ 450 ℃ and 425 ~ 452 ℃, respectively.