This study was aimed not only to develop the gill net and trap made of biodegradable monofilaments in order to prevent a ghost fishing and to protect marine ecosystem, but also to analyze their spinning process and physical properties. Results showed that the spinning speed of biodegradable polybutylene succinate(PBS) monofilament was estimated to be approximately 100m/min when spinning temperature and cooling water temperature were adjusted at $180^{circ}C$ and $3^{circ}C$, respectively. The breaking loads of PBS monofilaments were estimated to be $35.3kg/mm^2$ at ${phi}0.2mm$, $46.5kg/mm^2$ at ${phi}0.3mm$, and $49.7kg/mm^2$ at ${phi}0.4mm$ in the dry condition, respectively. However, its breaking loads in the wet condition were reduced by 2.4-5.5%, compared to those in the dry condition. The knotted strength of PBS monofilament at ${phi}0.2mm$ was estimated to be 98.6% of PE in the dry condition. The breaking load of PBS monofilament at ${phi}0.3mm$ was evaluated to be 81.8% of PA, and its softness showed 3 times less than that of PA in the wet condition. The breaking load of PBS monofilament at ${phi}0.4mm$ was 95.3% of PA, and its softness showed 1.6 times less than that of PA in the wet state. However, the load elastic elongations of two kinds of monofilaments were estimated to be 1% higher than that of PA.