Food and nutrition security remain at the top of development priorities in low income countries. This is especially the case for smallholder farmers who derive their livelihood from agriculture yet are often the most deprived. Inclusive agribusinesses have been championed as a key strategy to address local constraints that limit smallholders’ participation in regional and global value chains, thereby enhancing their livelihood, and food and nutrition security, accordingly. In this paper, based on a mixed method research approach, we explore the potential food and security contribution of inclusive agribusiness in Makueni county, Kenya. We focus on the smallholders’ constraints and needs, exploring the extent to which these are addressed by such purported pro-poor approach. First, using independent sample t-tests and a probit regression model, we explore who are able to participate in an ongoing intervention. We compare how participants and non-participants differ in terms of key socio-economic characteristics and establish which of these attributes are associated with successful integration into the business. Second, we again use independent sample t-tests to determine how the participants and non-participants compare in terms of their food and nutrition security. The household food and nutrition security is assessed with the conventional measurement tools: the household food insecurity access scale and the household food dietary diversity score. We find that participation in the inclusive agribusiness favors smallholder households with relatively higher production capacity in terms of better physical capital (land and number of mango trees, financial capital), access to loans, and human capital (age, education, and family size). Following income improvement, the participants’ household food security situation is significantly better than for non-participants. However, participation does not improve household dietary diversity, implying that improvement in income does not necessarily lead to better household nutrition security. To address the limitations of inclusive agribusiness, we propose policymakers and development actors to critically explore the contextual background prior to intervention design and implementation, and accordingly devise a broader approach for more inclusivity of the very poor and marginalized, and better food and nutrition security outcomes as a result. Given that not every smallholder could benefit from inclusive agribusiness for their food needs due to resource scarcity, alternative livelihood supports, including social protection programs and safety net plans, should be considered.