Plant-derived bioactive attains increasing attention due to their advantages such as high target specificity, low production cost, and strong tissue permeability. While earlier research primarily focused on peptides from plant-derived high-protein foods, recent years have witnessed a growing interest in peptides from plant-derived low-protein foods. The systematic exploration of bioactive peptides in such foods not only expands the sources of bioactive peptides, but also promotes the diversification of food resources through the development of novel food matrices. This article first discusses the peptidomics-based analytical workflow for identifying peptides in plant-derived low-protein foods, with a focus on three key steps: extraction and enrichment, detection and analysis, and bioactivity prediction. It then reviews the main bioactive peptides found in these foods, including anti-hypertensive, lipid-lowering, hypoglycemic, antioxidant, and anti-inflammatory peptides. Future research on bioactive peptides from plant-derived low-protein foods should shift from single-activity prediction and in vitro validation toward systematic studies encompassing synergistic effects, in vivo mechanisms, and processing stability. This study provides a methodological framework for mining bioactive peptides from plant-derived low-protein foods and offers insights for the development of related food resources.