Biocultural approaches are gaining attention for coping with current sustainability challenges. These approaches recognize that biological and cultural diversity are inextricably linked. Indigenous and local knowledge (ILK) plays an important role in biocultural approaches as these often build on local cultural perspectives. This review explores how ILK is conceptualized and applied in the scientific literature published in Spanish on biocultural approaches to sustainability and examines the status and trends of ILK described in this literature. For this, we reviewed 72 publications and conducted a category-based qualitative content analysis. We found multiple conceptualizations of ILK, although most of them shared some commonalities, such as the close link to specific biocultural contexts. The results suggests that there are three themes that seem to be both relevant and controversial within the reviewed literature: the different strategies to bridging diverse knowledge systems, the conflictive views on the role of ILK in sustainability, and the threats to ILK. We also show that future research would benefit from greater attention to power relations and context-specific dynamics in bridging diverse knowledge systems, as there is still room to improve approaches and tools to promote the co-production of knowledge while supporting and enhancing the self-determination of IPLC. We conclude that the way biocultural approaches to sustainability engage with ILK can support shape a variety of alternative futures, which may differ from currently dominant perspectives on sustainability, and further demonstrate that the design and implementation of conservation policies that protect both people and nature can be enhanced.