Nature-based Solutions (NbS) are becoming more popular in the current time to address the complex issues of climate change, biodiversity loss and food security in agro-ecosystems. In this systematic review, we synthesize existing empirical research on NbS in agriculture, focusing on their effectiveness, implementation difficulties, and potential for upscaling. Employing a rigorous methodology aligned with PRISMA 2020 criteria, we screened 2,900 records from Web of Science, Scopus, and Google Scholar. We included 83 studies (65 empirical, 10 meta-analyses, and eight policy documents) after quality assessment. The analysis demonstrates that NbS practices make a considerable contribution to carbon sequestration, with reported rates ranging from 1.8 to 133 Mg C ha⁻¹, depending on the practice and setting. Substantial benefits in biodiversity, including increases in pollinator populations and soil microbial richness, are also routinely seen. Economically, NbS provides significant returns on investment, with specific practices earning over £4 for every £1 invested and short payback times. Despite these benefits, widespread adoption is limited by a considerable 60% finance gap, compounded by large agricultural subsidies that generally favor conventional approaches. This review identifies explicit geographic and thematic biases, with most studies concentrated in temperate regions and focused on carbon and biodiversity, while tropical systems, arid zones, and economic or social outcomes remain underexplored. We conclude that realizing the transformative potential of NbS requires standardized MRV systems, better valuation of non-market benefits, redirection of subsidies, and integrated policy and financing frameworks that align ecological function with long-term economic sustainability.