Wild indigenous vegetables are underrecognized components of traditional food systems that may contribute to agrobiodiversity, dietary diversification, and food-system resilience. This study synthesized global ethnobotanical evidence on wild indigenous vegetables, focusing on diversity, geographic distribution, edible plant parts, preparation methods, and medicinal relevance. A systematic search of Scopus was conducted for English-language peer-reviewed articles published from 2006 to 2026. Following PRISMA-based screening, 90 studies were included, and extracted data were standardized taxonomically and analytically. The final dataset comprised 1,878 unique species. The highest documented richness occurred in China, India, Turkey, Pakistan, Bosnia and Herzegovina, and Croatia. Asteraceae was the dominant family, followed by Fabaceae, Brassicaceae, Lamiaceae, Apiaceae, Polygonaceae, Poaceae, and Amaranthaceae. Wild vegetable use was dominated by multiple plant parts, leaves, and shoots/stems, while cooking as vegetables was the most common preparation method, followed by raw/fresh consumption, soups/stew, and stir-frying/frying. Food-only use accounted for 77.6% of species, whereas 22.4% had both food and medicinal uses. Gastrointestinal applications were the most frequently specified medicinal category. These findings show that wild indigenous vegetables represent a diverse, multifunctional, and culturally important pool of underutilized food resources requiring further nutritional, phytochemical, ecological, and conservation-based research.