Ankle orthoses are commonly used for protection against initial ankle sprain injuries and for protection against reinjury. The purpose of this study was to compare the effects of the DonJoy Ankle Ligament Protector (ALP) and the Aircast Sport-Stirrup (AS) on the functional performance tasks of a 40-meter sprint, a figure-of-eight run, and standing vertical jump. Subjects were 14 males and nine females who reported a history of two or more lateral ankle sprains of the same ankle and no sprains of the contralateral ankle. Each subject performed all functional tasks on the first test day with both ankles unbraced and with the recurrently sprained ankle braced with one of the two orthoses. Each subject returned for testing on a second day and performed all tasks with both ankles unbraced and with the other orthosis on the recurrently sprained ankle. Subjects also rated the orthoses for comfort and support. Analysis of variance indicated that braced data were not significantly different than unbraced data and that data for the two orthoses did not differ significantly for any of the functional performance tasks. Seventy-four percent of the subjects reported the AS was more comfortable than the ALP, and 61% of the subjects indicated that the AS provided more support than the ALP. Neither orthosis had an effect on functional performance. The results may assist clinicians in selecting either of these orthoses for use in protection against ankle sprain injury.