Tuna has a significant economic value in the world and is the third largest fishery commodity in Indonesia after shrimp and demersal fish. Tuna has a relatively high price compared to other fish commodities, and its demand continues to increase. Fishing gear suitable for catching large pelagic fish, such as tuna includes the handline fishing gear. Fishermen commonly use tuna handlines for this purpose, and Maluku fishermen specifically use them to catch the yellowfin tuna. However, tuna caught with handlines often face predation from other fish, and their quality diminishes as they struggle to escape. To improve the quality of the caught fish, a device known as the "tuna jacket" has been introduced. This handling device serves as a protective cover for fish under attack or being eaten by other fish. Additionally, the tuna jacket restricts the movement of captured fish, leading to their quicker death. This research aimed to analyze the effectiveness of using tuna jackets in handline fisheries in Maluku waters, Indonesia. The study's results indicate that tuna jackets are more effective compared to the control methods. However, fishermen have a negative perception of the tuna jacket since its use can reduce their income.