Indigenous women are important part of a community’s social capital. This study examined women’s use of Indigenous knowledge (IK) for environmental security and sustainable development in southwest Nigeria. Qualitative data was collected using in-depth interviews conducted among 80 purposively selected rural Yoruba women. The data were analysed using descriptive tools such as frequencies, percentages, and content analysis. The findings reveal an extensive wealth of IK used in agriculture, food processing and preservation, family health care, and child care. The findings also suggest that paying attention to IK will help to incorporate culture as part of rural development and sustainable development in Nigeria, leading to more successful outcomes using place-based knowledge. Indigenous women can, and should, contribute to the design and implementation of sustainable development initiatives because of their extensive IK.