Introduction: Clear postural deficits and impairments throughout the gait cycle have been shown in chronic ankle instability (CAI) patients. The potential causes for these deficits remain unknown but both centrally or peripherally mediated mechanisms have been hypothesized. A dual task interference (DTI) paradigm, such as walking with an additional cognitive task, may provide a better understanding of central influences contributing to the gait impairments observed in CAI patients. Objective: The purpose of this study was to identify if DTI during gait effects individuals with CAI differently compared to healthy uninjured controls. Methods: Seventeen participants volunteered for this investigation (9 CAI, 7 healthy). First, participants practiced the cognitive task, backwards counting by 7s. Participants the performed 6 walking trials (3 baseline, 3 DTI) at a set speed of 3.86 kph. All walking trials were 60-seconds in length and delivered in a random order. Each trial was separated by a 20-second transition period which required participants continue walking on the treadmill without any cognitive load. During the DTI trials, participants counted backwards by 7s from a pseudo-random three-digit number (e.g. 683) as quickly and accurately as possible. Gait parameters were collected using an OptoGait (Microgate, Bolzano, Italy) floor-based photocell system and included the proportion of gait cycle spent in double limb stance (%), step length (cm), and step time (sec). Participants wore noise cancelling head phones during all walking trials to minimize distractions. Separate repeated measures ANOVA were used to examine the effects of Group x Task on walking gait parameters. An alpha level of p<0.05 was used for all statistical analyses. Results: No significant differences between healthy and CAI participants were made in double limb support percentage at baseline (Healthy Baseline:0.44+0.057; CAI:0.49 ±0.059) and (Healthy CT:0.44+0.064; CAI:0.49+0.059). Step times for each group were equal in both baseline and cognitive task (Healthy:0.58+0.03s; CAI:0.61+0.05s). No significant difference reported in step length (Healthy Baseline 56.52+5.18cm; CAI:52.74+4.71cm) and (Healthy CT:56.43+5.30cm; CAI:52.63+4.67cm). Conclusions: Preliminary data suggest there are no differences between healthy and CAI participants based on the means and standard deviations.