Background <p>Parkinson’s disease (PD) is an incapacitating progressive neurological disorder that exerts a significant effect on quality of life. There is no cure, so current treatments aim to decrease symptoms due to central nervous system dopamine deficiency.</p> Purpose <p>The study was to monitor how transcranial photobiomodulation (tPBM) improved patients with Parkinson’s disease.</p> Methods <p>A randomized controlled trial study, where thirty-eight patients of both genders, aged 50–70 years, suffering from postural instability and limited functional activity level due to PD, were randomly assigned to two groups: group A of the experimental group was treated with transcranial photobiomodulation (tPBM), and group B of the control group was provided with standard treatment. All the assessments were conducted before and after the 12-week treatment schedule.</p> Results <p>Statistically significant differences in limit of stability and functional level of the experimental group were observed in favor after 3 months of training (<i>P</i> &lt; 0.05).</p> Conclusion <p>tPBM might be effective in improving posture stability and functional activity level of Parkinson’s disease patients.</p>