Abstract: Metal foam possesses a large heat transfer surface area due to its porous structure, making it an excellent heat transfer material. Enhanced heat transfer can be achieved by combining metal foam with various heat exchange methods. The principle of field synergy focuses on the interaction between the flow field and the temperature field. It is a method that explains the causes of heat transfer in fluid flow by leveraging the correlation between flow and heat transfer. To elucidate the enhanced heat transfer mechanism of metal foam heat sinks, the influence of metal foam heat sinks on the heat exchange performance of impinging jets is investigated based on the field synergy principle. The synergy angle indicates that the secondary recirculation vortex is the primary cause of changes in the flow field and temperature field influenced by metal foam. Advancing the secondary recirculation vortex enables more intense heat exchange. The characteristic number equation corroborates the influence pattern of metal foam pore properties. To further illustrate the application of field synergy principles in guiding the optimization of heat transfer structures, numerical simulations are conducted to investigate the influence of structural parameters on the heat transfer performance of microchannel metal foam fin heat sinks. Heat transfer structures with uniform flow and temperature distributions enable enhanced heat transfer. Rational performance evaluation metrics are pivotal for optimizing metal foam heat sink designs. Both an increased Nusselt number and a reduced synergy angle effectively characterize improvements in heat sink performance.