As complex ecological systems managed for agricultural production, agroecosystems are deeply influenced by biodiversity, which is crucial for maintaining productivity, sustainability, and soil health. This chapter delves into the vital role of biodiversity, encompassing genetic, species, and ecological diversity, in sustaining agroecosystems. Biodiversity within these systems offers numerous benefits, including enhanced nutrient cycling, improved soil fertility, effective pest and disease management, and increased resilience to environmental stressors. The chapter explores how land-use changes, such as tillage, erosion, and alterations in plant species, can significantly impact soil biodiversity, often leading to reduced soil fertility and increased reliance on fertilizers and pesticides. The importance of traditional and underutilized crops, crop wild relatives, and diverse cropping systems, such as agroforestry and polycultures, in promoting agrobiodiversity is emphasized. These systems play a key role in maintaining soil health and Biodiversity by supporting a dynamic soil food web that includes various microorganisms and invertebrates critical for decomposition and nutrient cycling. Furthermore, the chapter highlights the necessity of implementing sustainable management practices, such as crop rotation, conservation tillage, and integrated pest management, to foster Biodiversity and enhance ecosystem services. The impact of invasive species on soil biodiversity and ecosystem functioning is also addressed, emphasizing the need for effective management strategies. By preserving and enhancing Biodiversity, agroecosystems can achieve greater productivity, ecological balance, and long-term sustainability. This, in turn, contributes significantly to global food security and environmental health, ensuring the resilience of agricultural systems in the face of global changes.