Two types of main-chain type polybenzoxazines with amide and benzoxazine groups as repeating units in the main chain, termed as poly(amide-benzoxazine), have been synthesized. They have been prepared by polycondensation reaction of primary amine-bifunctional benzoxazine with adipoyl and isophthaloyl dichloride using dimethylacetamide as solvent. Additionally, a model reaction is designed from the reaction of 3,3'-(4,4'-methylenebis(4,1-phenylene)) bis(3,4-dihydro-2H-benzo[e][1,3]oxazin-6-amine) with benzoyl chloride. The structures of model compound and polyamides are confirmed by Fourier transform infrared (FTIR) and proton nuclear magnetic resonance ((1)H NMR) spectroscopies. Differential scanning calorimetry and FTIR are also used to study crosslinking behavior of both the model compound and polymers. Thermal properties of the crosslinked polymers are also studied by thermogravimetric analysis. (C) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 4335-4342, 2011