Abstract: Highly purified bio-based butyrolactam (BBY) was prepared at about 97.7% purity from biologically derived γ-aminobutyric acid (GABA) by high temperature hydrolysis and rectification under vacuum. The purified BBY was used as the monomer to prepare bio-based polybutylactam (BPBY) by anionic ring-opening polymerization. The structure of BBY and BPBY were characterized by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR). High performance liquid chromatography (HPLC) was used to analyze the purity of BBY and bio-mass spectrometry (BMS) was used to measure the relative molecular mass of BPBY. In addition, differential scanning calorimetry (DSC) was used to compare the thermal properties between BPBY and petroleum-based polybutyrolactam (PPBY). Furthermore, tensile test and aging degradation test were carried out to find the differences between BPBY and PPBY. The results showed that BPBY was synthesized successfully from GABA by two main processes. The relative molecular mass of BPBY was lower than that of PPBY. The glass transition temperature and melting point of BPBY were 102.3℃ and 203.8℃, respectively. Tensile strength and elongation at break of BPBY film were 20.32 MPa and 8.78%, respectively. Although the relative molecular mass, thermal and mechanical properties of BPBY were not as good as PPBY, these properties were close between two materials, meaning that BPBY can replace PPBY in some conditions. In addition, the degradability of BPBY was 17.56% (mass fraction) in 30 d, which was faster than that of PPBY. BPBY is eco-friendly compared with PPBY and it could be used to solve the white pollution problem.