Derelict fishing gears (DFGs) present a high damage risk for marine ecosystems, navigation safety, fishing resources, and the economy. To mitigate this damage, considering fishers’ roles is very important, because they are the main contributors directly exposed to the impact. Since DFGs are significant sources of marine debris in South Korea, we conducted a survey to evaluate fishers’ perception of DFGs’ causes, reasons, and measures, based on FAO’s and UNEP’s 2009 suggestions. We also examined which governmental measures they preferred to help decrease DFGs. A total of 134 people participated in the 2015 survey, comprising 55 from capture fishing and 79 from aquaculture. The fishers answered that DFGs are abandoned, discarded, and lost in similar proportions. In terms of abandoned DFGs, they selected similar degrees of impact regarding ‘illegal, unreported andunregulated fishing,’ ‘illegal gear,’ and ‘too much gear for time.’ For discarded DFGs, they mostly agreed that ‘chosen over onshore disposal’ and ‘damaged gear’ were more serious causes than ‘too much gear for space.’They answered that ‘misplaced gear’ causes less lost DFGs than ‘gear conflict,’ ‘poor ground condition,’ and ‘extreme weather.’ In total, the fishers found ‘improving port facilities’ and ‘retrieval activities’ as more effectiveand feasible measures than others. They positively evaluated the Korean government’s existing measures, and preferred ‘mandatory return’ and ‘strengthening gear marking’ for future improvement measures. This study couldfurther contribute to achieving policy goals more effectively and efficiently.