In December, 1990, the N.S.W. Minister for Agriculture and Rural Affairs removed the Pacific oyster (Crassostrea gigas) from the noxious fish list for the Port Stephens area, permitting it's cultivation. As Port Stephens Pacific oysters are grown intertidally, similar to Sydney rock oysters (Saccostrea commercialis) there was a belief that they may have different storage requirements to overseas Pacific oysters which are cultivated in deep water exclusively. Consequently, the keeping quality of this oyster and it's compliance with N.S.W. bacteriological regulations were examined. Port Stephens Pacific and Sydney rock oysters were purified, then stored at refrigeration and ambient temperatures. Levels of faecal coliforms, standard plate count and Vibrio parahaemolyticus were determined daily. Pacific oysters were found to require refrigeration to extend shelf life. At 5 degree C, Pacific oysters survived up to 14 days, whereas at ambient temperature (23 degree C) they started to gape and die after 4 to 8 days. The level of V. parahaemolyticus generally decreased with increasing storage time for Sydney rock oysters at 23 degree C and 5 degree C. No general decrease was observed with Pacific oysters, where 2.4 x 103 V. parahaemolyticus /g were detected after 14 days at 5 degree C.