Background <p>Previous studies have confirmed that plant and dairy proteins help with hepatic encephalopathy; yet, the impact on oxidative stress and inflammation in liver cirrhosis remains unexplored. This is the first interventional clinical trial investigating the impact of a plant and dairy protein diet on oxidative stress and inflammatory biomarkers in cirrhotic patients.</p> Methods <p>In this controlled randomized clinical trial, 46 patients with cirrhosis were divided into two groups to receive a prescribed diet based on vegetable and dairy proteins (intervention group, <i>n</i> = 23) or a standard isocaloric diet (control group, <i>n</i> = 23) for 12 weeks. Anthropometric indicators, physical activity level, inflammatory biomarkers including serum levels of high sensitive C-reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-α), and interleukin 6 (IL-6), as well as oxidative stress status including serum malondialdehyde (MDA), total antioxidant capacity (TAC), and total oxidant status (TOS) were evaluated before and after the intervention. Dietary intake was also assessed before, during, and after the intervention.</p> Results <p>Based on the findings of this study, consuming a diet based on plant and dairy protein significantly reduced the Model for End-Stage Liver Disease (MELD) score (<i>P</i> &lt; 0.05). No significant changes were observed in anthropometric parameters, including body mass index, mid-arm muscle circumference, and triceps skinfold thickness, as well as serum levels of inflammatory biomarkers (hs-CRP, TNF-α, and IL-6) and oxidative stress biomarkers (MDA, TOS, and TAC).</p> Conclusion <p>Following a diet based on plant and dairy proteins for 12 weeks in patients with cirrhosis caused a reduction in MELD score, which may indicate meaningful clinical improvement in disease severity even without significant changes in inflammatory and oxidative stress biomarkers.</p> Trial registration number <p>IRCT20220426054667N3, this trial was registered on July 2, 2023.</p>