New N-phenylated aromatic-aliphatic and all aromatic polyamides were prepared by the high-temperature solution polycondensation of 4,4＇-dianilinobiphenyl with both aliphatic (methylene chain lengths of 6-11) and aromatic dicarboxylic acid chlorides. All of the aromatic-aliphatic polyamides and the wholly aromatic polyamides exhibited an amorphous nature and good solubility in amide-type and chlorinated hydrocarbon solvents, except for those aromatic polyamides containing p-oriented phenylene or biphenylylene linkages in the backbone; the latter were crystalline and insoluble in organic solvents except m-cresol. The N-phenylated aromatic-aliphatic polyamides and aromatic polyamides had glass transition temperatures in the range of 79-116 degrees C and 207-255 degrees C, respectively, and all the polymers were thermally stable with decomposition temperatures above 400 degrees C in air.