Poly(1,3-propanediol-sebacate) oligomers were synthesized under relatively low temperature without any catalysts. GPC chromatograms showed that the coarse products often presented multi-components because of the excess 1,3-propanediol, but they gradually became homogeneous with the dosage decrease of 1,3-propanediol. FTIR spectra demonstrated that the main chains of the oligomers were formed by ester bonds, and the contents of hydroxyl groups tended to drop down as the molar ratio of monomers decreased and the second-stage reaction was carried out. Based on the 1HNMR analysis, it was found that the actual molar compositions of the oligomers were much lower than the initial molar ratios of monomers, and their molar mass ranged from 967.14 to 3970.49 g/mol, and the terminating degrees from 1,3-propanediol were within 38%~66%. The oligomers were expected to be used as nontoxic, environment-friendly and biodegradable plasticizers in preparation of chewing guns.