Currently, a growing focus is devoted to the creation and utilization of renewable resources for bio-based polyesters due to the shortage of oil resources. Since 2,5-furandicarboxylic acid (FDCA) has been described as one of the most promising platform compounds, FDCA-based polyesters have been rapidly developed. Poly(decylene terephthalate- co -decylene furandicarboxylate) (PDTFs) in this study were prepared from dimethyl terephthalate (DMT), 1,10-decanediol (DDO) and dimethyl 2,5-furandicarboxylate (DMFD). By using 1 H NMR and 13 C NMR, the polyesters' chemical structure was verified. The thermal properties and the thermal stability of the polyesters were analyzed by Differential Scanning Calorimetry (DSC) and Thermogravimetric analysis (TGA). All polyesters underwent mechanical testing to ascertain their Young's modulus, tensile strength, and elongation at break. All polymers are semi-crystalline materials. The crystal texture of PDTF24 is equivalent to that of poly(decylene terephthalate) (PDT). However, the crystal structures of PDTF48 and PDTF76 are similar to that of poly(decylene furandicarboxylate) (PDF). All polymers exhibit high thermal stability. PDF has the highest tensile strength, probably because the oxygen atom on the furan ring results in stronger intermolecular interactions. When the content of the decylene furandicarboxylate unit reaches 48%, Young's modulus reaches its lowest value (96.6 MPa), but its elongation at break reaches its highest value (1098%) due to the lowest crystallinity. • A series of bio-based copolyesters have been successfully synthesized from dimethyl terephthalate (DMT), 1,10-decanediol (DDO) and dimethyl 2,5-furandicarboxylate (DMFD). • The effects of composition on microstructure, thermal properties, and mechanical properties were investigated. • The crystal structure of PDTF48 and PDTF76 are comparable to PDF and PDTF24 is analogous to the crystal structure of PDT. • PDF has the highest tensile strength, which should be attributed to strong intermolecular interactions caused by the oxygen atom in the furan ring.