Drosophila suzukii Matsumura, or spotted wing drosophila (Diptera: Drosophilidae), is a fly that is believed to be native to Japan. Spotted wing drosophila females lay eggs into ripe and ripening soft skinned fruits, where larvae develop. The species was first found in the continental United States in 2008, where it was reported to cause extensive economic damage in many fruit crops, including raspberry, blackberry, blueberry and cherry. Spotted wing drosophila is believed to overwinter as a seasonally acclimated winter morph adult. While spotted wing drosophila is found in northern states with colder climates, the ability of it to establish and overwinter in these regions is unknown. Likelihood of spotted wing drosophila overwintering survival was hypothesized by reviewing literature on other Drosophila species cold tolerance. Cold tolerance of spotted wing drosophila was then measured by comparing the supercooling points and lower lethal temperatures of seasonally acclimated (winter-morphs) and non-acclimated adults (summer-morphs). The ability of winter-morphs and summer-morphs to rapidly cold-harden was also studied to determine if the fly can quickly acclimate to new cold temperatures.