Synthesis and molecular characterization of bisphenol A poly(iminocarbonate) were carried out. A successive precipitational fractionation and size exclusion chromatography measurement yielded well defined fractions whose molecular masses varied from 4,000 to 62,300 g/mol. Dilute solution viscometry in both the systems of θ-composition and DMF at 30℃ confirmed the viscosity-molecular mass relationship is well outside the Gaussian behavior. The chain parameters found on the basis of wormlike cylinder model were: M_L=473 nm^-1, persistence length q=1.8 nm, and cylinder diameter d=0.92 nm, which appeared slightly higher than those of bisphenol A polycarbonate. These led to a conclusion that the chains can be regarded as semiflexibel with less stiff chain character.