Introduction: There is an early deterioration of balance and gait functions in Parkinson Disease (PD). In addition to this, participants with PD show deterioration in one or more cognitive areas. The combination of these results in more than 60% of PD participants reporting recurrent falls. To prevent such falls, there is a need to develop and validate an affordable rehabilitation program that targets both walking and executive cognitive performance in participants with PD. To answer this need, we have developed and validated, engaging, Game-based treadmill platform (GTP), which provides an integrated approach to assess and treat a decline in balance, mobility, visuomotor control and visuospatial executive cognitive function. Purpose: The primary purpose of this study was to examine the feasibility of the GTP program concerning the process, resources and management for conducting a future randomized controlled trial with GTP. The secondary purpose of this study was to evaluate the experience of the participant with the intervention program and provide an estimate of treatment effect size on various standing balance, gait and cognitive outcome measures. Methods: We aimed to recruit 20 participants with PD for the 10 weeks, twice a week GTP program. Standing balance, spatiotemporal gait variables and visuospatial search and visuomotor executive cognitive performance were evaluated at baseline and after 10 weeks of GTP intervention. Semi-structured interviews were conducted for all eligible participants to explore the user experience of the GTP program. Results: Fifteen participants diagnosed with PD, stage 1-3 on Hoehn and Yahr scale were screened for the study. All participants completed 10 weeks, twice a week dual-task intervention program with the GTP program. We observed excellent feasibility regarding recruitment, retention to program, study procedures and study management for conducting a future RCT with GTP. Medium to large effect sizes for all significant improvements in standing balance, gait, and cognitive performance were observed. Conclusion: We obtained favourable results for the feasibility of GTP to conduct RCT with an appropriate control group. The embedded semi-structured interviews also showed that GTP was highly appreciated among patients with PD. The substantial improvement in standing balance and gait of patients with PD shows the effectiveness of GTP for targeted rehabilitation.