Japanese spotted mackerels(Scomber tapeinoephalus) were stored at $0^{circ}C$ for 7days as the maximum, and then, they were stored again at $-3.5^{circ}C$(partial freezing) or $-20^{circ}C$(freezing), respectively. During storage by partial freezing, the fishes with a longer period of prestorage at $0^{circ}C$ showed an earlier increase in the number of bacterial cells on their skin, however, it was not apparent in the freezing storage. K value of the fishes with 7 days of prestorage increased from 20% to 65.4% for 36 days of partial freezing storage, that of the fishes prestored for 0 and 4 days were 39.9% and 53.2% respectively. On contrastly, no drastic increase in K value was observed in the fishes of freezing storage. Content of volatile nitrogen of the fish muscle prestored for 4 days gradually increased from 10mg% to 29.4mg% and 17.2mg% during 36 days of partial freezing and 83 days of freezing storage respectively, that of the fishes with 7 days of prestorage showed no significant increase, moreover, it was decreased within early period of both of the storages. Free drip from the fishes with partial fleering was higher almost 5 times than that from the fishes with freezing, the highest free drip was observed from the fishes with 4 days of prestorage.