This　study　investigates　the　structural,　mechanical,　and　thermodynamic　behaviors　of　AlSi2Sc2　under　uniaxial　tensile　loading　by　performing　first-principles　calculations　based　on　density　functional　theory.　The　parameters　of　the　lattice　a　and　c　were　found　to　depend　on　the　Al-Si　and　the　Sc-Si　bonds,　respectively.　Tensile　stress-strain　curves　were　used　to　obtain　ideal　tensile　strengths　of　16.1　GPa　and　21.2　GPa　along　the　a-and　c-axes,　respectively.　The　criteria　for　stability　showed　that　the　AlSi2Sc2　compound　became　mechanically　unstable　when　the　strain　exceeded　0.1　and　0.3　along　the　a-　and　the　c-axes,　respectively.　The　polycrystalline　elastic　constants　of　AlSi2Sc2　decreased　with　increasing　strain　along　both　axes　as　well,　as　did　its　Debye　temperature　and　minimum　thermal　conductivity.　An　analysis　of　its　electronic　structure　indicated　that　the　Al-Si　bonds　mainly　originated　from　the　hybridization　of　the　Al-3p　and　the　Si-3p　states,　whereas　the　Sc-Si　bonds　originated　from　the　Sc-3d　and　Si-3p　states.