Abstract: Understory planting is a sustainable development path for the transformation of ecological industrialization and industrial ecologicalization. To explore the research hotspots, trends, directions and planting differences of understory planting at home and abroad, this study analyzed 4,915 related documents downloaded from CNKI and Web of Science core databases from 1995 to 2024, using Citespce 6.3.1 and VOSviewer visualization analysis software to analyze the research frontiers, trends and differences of understory planting at home and abroad. The results show that: (1) From 1995 to 2024, the main regions of domestic understory planting were Southwest, South China, Northeast, East China and Northwest. Edible fungi and Chinese herbal medicines were the preferred plants. The research hotspots were cardamom, tropical rainforest and forest economy. The research frontiers have deepened from single crop planting to diversified models and integrated development of industries in the direction of regional economy. (2) From 1995 to 2024, the main regions of understory planting abroad were Asia, Europe, North America, South America and Africa. The plants were mostly coffee, corn and wheat. The research hotspots were agroforestry systems, non-timber forest products and management. The research directions have deepened from single crop cultivation and management to ecological fields such as biodiversity, ecosystem services, climate change and plant physiology and biochemistry. Overall, domestic research mainly explores the benefits brought by understory planting and its models from the perspective of regional economic development; while foreign research focuses more on the ecological field of agroforestry systems. In the future, domestic and foreign research can strengthen the exploration of ecological three-dimensional agriculture and forestry in the fields of mountains, water, forests, fields and lakes, enhance the utilization of resource space, and integrate scientific digital monitoring methods to establish a long-term food security monitoring mechanism.