This research aims to produce lignin-based biodegradable polyesters with improved thermal quality. A series of aliphatic polyesters with lignin-based aromatic side groups were synthesized by conventional melt-polycondensation. Decent molecular weight (21–64 kg mol−1 ) was achieved for the polymerizations. The molecular structures and thermal and mechanical properties of the obtained polyesters were characterized. As a result, the obtained polyesters are all amorphous, and their glass-transition temperature (Tg) depends on the size of the pendant aromatic group (31–51
C). Furthermore, according to the TGA results, the thermal decomposition temperatures of the polyesters are all above 390
C, which make them superior compared with commercial biodegradable polyesters like polylactic acid or polyhydroxyalkanoates. Finally, rheological characteristics and enzymatic degradation of the obtained polyesters were also measured.