Firmness and aroma composition of strawberry fruit (Fragaria ×ananassa Duch. cv. Pajaro) stored in air or treated with 20% CO2 for up to 12 days at 0C were analyzed upon removal from storage. Fruit firmness increased after 2 days in CO2, while the composition of aroma compounds in the fruit was unaffected at this time. Ethanol and ethyl hexanoate accumulated after 3 days during high CO2 treatment, but these compounds usually decreased during subsequent cold storage in air. Ethyl butanoate and ethyl acetate also accumulated but continued to increase after 6 and 9 days of CO2 storage, respectively. This study suggests that treatment of strawberry fruit with CO2 after harvest, followed by air storage at 0C, can maintain firmness while minimizing off-flavor development.