A series of bismaleimide monomers were used to prepare poly(aminobismaleimide)s in an attempt to achieve polymers with improved properties. Structurally different bismaleimides with ester units were synthesized by reaction between 3(4)-maleimidobenzoylchloride with various diphenols. Bismaleimides BMI-3 and BMI-4 were synthesized by reaction of maleic anhydride with diamines respectively. Polymers based on these bismaleimides were prepared by the Michael addition of diamines to bismaleimides. The monomers and polymers were characterized by infrared (IR) and proton nuclear resonance ( 1 H-NMR) spectroscopy. Thermal characterization of monomers and polymers was accomplished by differential scanning calorimetry (DSC) and dynamic thermogravimetric analysis (ATG).