In this study, an attempt was made to prepare bio-based poly(pentamethylene oxamide) (PA52) using a novel process of spray/solid-state polycondensation. A prepolymer of relative viscosity of 1.3 was prepared by spray polycondensation, where the monomers (dibutyl oxalate and 1,5-pentanediamine) were separately injected into the nozzle, atomized simultaneously under nitrogen flow, mixed, and polymerized at room temperature. After solid-state polycondensation, PA52 with relative viscosity of 3.2, weight-average molecular weight of 4.3 x 10(4), and melting point of 301 A degrees C was obtained. FTIR and H-1-NMR analysis confirmed the formation of PA52 while the DSC results suggested that the resultant polymer possessed high heat resistance and good crystallizability.