Hunger and malnutrition are major global challenges. Since the 2007–2008 food price crisis, both the Group of Twenty (G20) countries and the Group of Seven (G7) countries have launched various programs and initiatives on food security to tackle the challenges. This brief introduces the programs and initiatives undertaken by the G20 and the G7 on food security, highlights areas where both groups can work together, and points out ways to strengthen collaboration between the G20 and the G7. The G20 agenda on food security and agriculture focuses on improving the policy environment for agricultural production and productivity, trade, technology, youth employment, food loss and waste, and resilient food systems, and the G7 has acted as a donor group and focused on social protection, women’s employment, nutrition, and responsible investment. The G20 and the G7 are particularly important international arrangements that can play a catalytic role if they join hands together. This brief identifies six priorities for collaboration between the G20 and the G7, including embracing the food systems approach, increasing investment in science and innovation, reforming agricultural subsidies and trade, supporting the United Nations and other multinational agendas on food systems transformation, facilitating the science and policy interfaces, and ensuring accountability.