Purpose To investigate the efficacy of combining the dopamine receptor agonist pramipexole with levodopa for Parkinson’s disease (PD) treatment and to measure their effects on quality of life and tumor necrosis factor (TNF)-α levels in PD patients. Basic Procedure In total, 160 PD patients who were admitted to our hospital were equally randomized into a control treatment group (levodopa alone) and the study group (pramipexole combined with levodopa). Both groups were treated for 12 weeks. Findings After treatment, scores from the Unified Parkinson’s Disease Rating Scales (1–3), the Hamilton Depression Scale, and the Parkinson’s Disease Questionnaire (PDQ-39) were significantly decreased in both groups, whereas Mini-Mental State Examination scores were significantly increased. After treatment, the study group had significantly lower scores for all scales except the Mini-Mental State Examination, for which those who received combined treatment had significantly higher scores than the control group. The incidence of adverse reactions was significantly lower in the study group than in the control group. Furthermore, after treatment, serum TNF-α levels were significantly decreased in both groups compared with pre-treatment levels. Conclusion Pramipexole combined with levodopa relieved PD symptoms and improved the quality of life of PD patients, potentially by suppressing serum TNF-α levels.