N-trimelliticimido-l-aspartic acid (1) was prepared from the reaction of trimellitic anhydride with l-aspartic acid in a mixture of glacial acetic acid and pyridine solution (3/2 ratio) under refluxing conditions. The solution polycondensation of the corresponding activated monomer with eight aromatic diamines were carried out in DMAc. The resulting poly(amide-imide)s were obtained in quantitative yields, showed admirable inherent viscosities (0.20-0.36 dl g(-1)), good optical activity (+7.32A(0) to +15.24A(0)), and were readily soluble in polar aprotic solvents. They start to decompose (T (10%)) above 170 A degrees C and display glass-transition temperatures at 120-237 A degrees C. All of the above polymers were fully characterized by UV, FT-IR, and (1)HNMR spectroscopy, elemental analysis, thermogravimetric analyses, DSC, inherent viscosity measurement, and specific rotation.