Nonchemical quarantine treatments, using a combination of short duration high temperatures under low oxygen, elevated carbon dioxide atmospheric environment were developed to control western cherry fruit fly, Rhagoletis indifferens Curran, in sweet cherries, Prunus avium (L.). The two treatments developed use a chamber temperature of 45°C for 45 min and a chamber temperature of 47°C for 25 min, both under a 1% oxygen, 15% carbon dioxide, −2°C dew point environment. Both these treatments have been shown to provide control of all life stages of western cherry fruit fly while preserving commodity market quality. There was no definitive egg or larval stage, which was demonstrated to be the most tolerant to either controlled atmosphere temperature treatment system treatment. Efficacy tests for both treatments resulted in 100% mortality of >5,000 western cherry fruit flies in each treatment. These treatments may provide, with further study, quarantine security in exported sweet cherries where western cherry fruit fly is a quarantine concern and fumigation with methyl bromide is not desired.