This paper seeks to present methods for improving the occupational health and safety of Spanish fishermen, and for redesigning the workplace onboard small fishing vessels. To achieve its objective, the research project was designed in four steps: First, the equipment and procedures for catching, handling, and storing fish was studied. Second, the work postures of all the fishermen were simulated and assessed by using an ergonomic digital human modeling system (ManneQuin Pro). Third, the work environment design on board vessels was modified on the basis of acceptable simulated work postures to prevent repetitive movements and lower back biomechanical stresses. In the fourth and final step, ergonomic design parameters were provided to vessel designers.