The study focused on the mechanized catching of Larimichthys crocea bred in the aquaculture vessel. A prototype of the vacuum fish pump (VFP) was developed and then tested on the Guoxin 101 that was a pilot aquaculture vessel. The prototype was a single tank type,pre vacuuming process was adopted, and the knife gate valves were installed on the suction and discharge port of the tank, with the suction and discharge process controlled by liquid level mode. The experiments were carried out under the conditions of wave height of 1.00~1.40 m and obvious ship rolling and pitching. Firstly, the water absorption performance experiments under different suction heights and the fish catching experiment were carried out successively. The experimental fish were adult Larimichthys crocea with active swimming and undamaged appearance, randomly caught from the aquaculture cabin of the Guoxin 101. The water absorption performance experiments showed: with the increase of suction height, the suction discharge cycle time increased, and the vacuum degree in the tank of the VFP during the suction process increased, but the transportation rate of the VFP decreased. The fish catching experiment showed: under the condition of suction height of 2.30 m, it took 498 s by the VFP to catch 37.10 kg Larimichthys crocea completely; there was no obvious damage on the body surface of all the captured Larimichthys crocea, and most of the Larimichthys crocea captured by the VFP stilled maintain high active swimming. Therefore, it was feasible to use the VFP for mechanized catching Larimichthys crocea bred in the aquaculture vessel. [Chinese Fishery Quality and Standards, 2022, 12(6): 15- 20]