Thermomechanical　reliability　and　lifetime　of　solid-oxide　fuel　cells　are　significantly　influenced　by　thermal　mismatch　between　anode　and　electrolyte　layers.　This　study　presents　a　numerical　analysis　of　topology　optimization　of　the　microstructure　of　Ni–8YSZ　anode　to　minimize　the　thermal　mismatch　of　the　components.　We　obtain　two　2D　microstructures　by　taking　minimum　thermal　mismatch　as　object　function.　The　3D　microstructures　become　fibrous　and　orthogonal　by　stretching　the　2D　microstructures.　Results　show　that　the　coefficients　of　thermal　expansion　of　microstructures　in　the　plane　parallel　to　the　electrolyte　layer　are　almost　equal　to　those　of　electrolytes　from　room　temperature　to　800°C,　which　almost　completely　removes　the　thermal　mismatch.　Both　microstructures　have　high　three-phase　boundary　density,　which　is　almost　twice　or　five　times　that　of　a　typical　anode.　Compared　with　the　typical　anodes,　the　microstructures　have　higher　Ni–pore　interfacial　areas　and　ion　conductivities.　Optimization　results　are　helpful　in　the　design　of　future　electrodes.　©　2020　John　Wiley　&　Sons　Ltd