For　the　first　time,　this　paper　investigates　the　temperature-dependent　aerothermoelastic　properties　of　nano-composite　pyramidal　lattice　sandwich　beams　in　supersonic　airflow.　A　nonuniform　temperature　distribution　along　the　thickness　is　considered.　The　face　sheets　and　core　of　the　sandwich　beam　are　fabricated　from　graphene　platelet　(GPL)-reinforced　nanocomposites.　A　refined　thermo-mechanical　equivalent　model　is　established　to　determine　the　effective　shear　modulus　of　the　lattice　core　subjected　to　a　nonuniform　temperature　distribution.　Then,　the　core　transforms　into　a　continuum　layer.　Subsequently,　the　beams　with　lattice　cores　were　modeled　as　equivalent　sandwich　structures　composed　of　three　continuum　layers.　The　effective　modulus　of　elasticity　of　the　nano-composites　was　calculated　using　the　Halpin-Tsai　micromechanics　model　combined　with　the　mixture　rule.　The　aerodynamic　pressure　was　calculated　using　the　first-order　supersonic　piston　theory.　The　aerothermoelastic　properties　of　the　sandwich　beam　were　investigated　by　analyzing　the　critical　flutter　aerodynamic　pressure　and　time-dependent　responses　of　structures.　The　influences　of　nonuniform　temperature　distribution,　GPL　re-inforcements,　and　end　restrictions　on　the　flutter　characteristics　of　beams　are　addressed　using　some　parameter　examples.