New material design and microstructure control are key issues to advance current fuel cell systems. To satisfy high requirements of efficiency and power density, further accelerations of electrode reaction and ionic conductivity should be investigated. This report reviews oxide materials for electrode and electrolyte of solid electrolyte fuel cells, especially focusing on control over surface and interfacial microstructures. The formation of heterointerfaces is effective approach to accelerate electrode reaction and ionic conductivity. Ion transport phenomena at heterointerfaces provide new insights, which can suggest potential applications in fuel cell systems.