The production amount of wakame seaweed (Undaria plnnatiflda) in Japan has declined with wakame aquaculture households decreasing. The wakame aquaculture tasks, that are harvesting on board and processing of the salted seaweed product on shore, are concentrated in a period of one month. Especially the harvesting operation is a heavy task, so labor saving measures will be required. In this report, workload analysis methods, such were Ovako working posture analyzing system (OWAS) and low back compression values for human body, were applied for the examples of the harvesting on board. The OWAS workload indexes were approximately in good agreement with the low back compression values. Comparison of workload analysis by OWAS among three types of fishermen's harvesting tasks at Sanriku district, the work efficiencies were strongly affected by AC scores from the OWAS method.
