Polycystic kidney disease (PKD) is a genetic disorder characterized by progressive kidney cyst formation and eventual kidney failure. Emerging evidence suggests that plant-based diets may confer therapeutic benefits in patients with PKD by modulating mTOR and AMPK signaling, reducing oxidative stress and inflammation, while improving metabolic and cardiovascular profiles. These diets, which are low in animal protein and rich in antioxidants, may help lower uric acid levels and support blood pressure control, thereby potentially reducing fibrosis. However, careful planning is required to avoid nutritional deficiencies. Well-designed clinical trials are warranted to validate their role in ADPKD management.