The potential utilization of leaf, stem, root, and tuber vegetable by-products as natural sources of bioactive compounds has attracted interest among researchers in recent years. Leaf, stem, root, and tuber vegetables are quotidian constituents of the food cycle worldwide, generating copious quantities of by-products. These by-products are often discarded without any treatment, leading to concerns about sustainable utilization. Hence, the assessment of potentiality among these by-products has become obligatory. Many edible leaf, stem, root, and tuber vegetable by-products are already being utilized in various forms for human consumption. Recent research endeavors have been focused on exploring the potential of bioprocessing of the by-products into value-added bioproducts for food, feed, nutraceutical, pharmaceutical, biotechnological, and bioenergetic applications. Besides daily consumption, vegetables have emerged as major sources of bioactive compounds that contribute to the reduction of several chronic diseases and health maintenance. This work highlights the current situation and valorization potential of leaf, stem, root, and tuber vegetable by-products.