A series of new poly(enaminonitriles) were synthesized by the condensation polymerization of three different bis(chlorodicyano-vinyl) aromatic monomers with various aromatic diamines. These polymers have moderate to high molecular weight with intrinsic viscosities ranging from 0.35 to 0.77 dl/g and form flexible films. These polymers exhibit good solubility in many organic solvents and excellent thermal stability, retaining their weight up to 400 °C in air. Poly(enaminonitriles) undergo ‘curing’ reactions at high temperature (˜300 °C) to provide insoluble, infusible material without emission of volatile by-products. Dielectric constants of these polymers ranged from 3.5 to 5.2 depending on the structure. Their thermal and dielectric properties are correlated to the structures.