The clinical presentations of Parkinson's disease (PD), a chronic neurodegenerative condition, include bradykinesia, hypokinesia, stiffness, resting tremor, and postural instability. Recently, neuroinflammation is involved in pathogenesis of PD. Application of nonsteroidal anti-inflammatory drugs captured attention to treat these neuroinflammation. To investigate the possible effectiveness of celecoxib in patients with PD treated with conventional treatment. Sixty outpatients who fulfilled the inclusion requirements for PD were enrolled in this randomized, prospective, and controlled study. The patients were allocated into two groups at random (n = 30); the control group received standard PD treatment, consisting of levodopa/carbidopa, and the celecoxib group received standard PD treatment plus celecoxib. A neurologist evaluated each patient at the beginning of the treatment and after 6months. Assessment of Unified Parkinson's disease rating scale (UPDRS) for each patient. Before and after treatment, α -synuclein (α-Syn), tumor necrosis factor alpha (TNF-α), Toll like receptors-4 (TLR-4), nuclear factor erythroid 2-related factor 2 (Nrf-2) and brain-derived neurotropic factor (BDNF) were assessed. Paired and unpaired t tests were used to assess statistical significance within and between groups respectively. The celecoxib group exhibited a significant and statistical reduction in the level of measured parameters by unpaired t test as followed: TLR-4 (p = 0.004), TNF-α (p = 0.042), and α-Syn (p = 0.004) apart from a significant increase in BDNF (p = 0.0005) and Nrf-2 (p = 0.004), in comparison with the control group. Also, UPDRS was significantly decreased in celecoxib group (p < 0.05). Celecoxib could be a promising adjuvant therapy in managing patients with PD. NCT05962957.