Physical characteristics of PA (Polyamide) gill net and biodegradable gill net made by PBS (Polybutylene succinate) (mesh size 63mm, mesh thickness number 2, 2.5, 3) were analyzed to investigate catching efficiency of the biodegradable gill net for Pacific herring. Total 11 numbers of catching efficiency tests were carried out using commercial fishing vessel at Imwon port in Kangwon province from May to June 2013. The amount of catches were 1,535.7kg (18 species) through the catching efficiency tests and it is expected that the practicalization of biodegradable gillnet is possible because there is no difference for catches between PA gillnet and PBS gillnet. Catches of herring according to the thickness of net twine was the highest at No.2 and the thicker net twine tends to decrease the catches.