Abstract: A continuous output brine freezing system is disclosed particularly applicable to the freezing of large fish such as tuna on board fishing vessels. The vessels include a series of fish freezing tanks within which the large fish, after being encapsulated in plastic bags and vacuum sealed, are loaded and frozen in sequence. One of said tanks is a brine storage tank and has means of precooling the brine to a temperature of -35.degree. C. Means are provided for feeding the precooled brine from the first tank to the next tank in line and to the remaining tanks in sequence as the tanks are loaded with fish. Means are also provided to remove the brine from the tanks in sequence and to return the brine to the first tank as the fish are frozen. Means are provided to maintain the quality of the brine and to recycle the brine through the system as fish are brought on board and loaded into the tanks, and to unload the frozen fish from the tanks by flotation with brine.