Tight　sandstone　gas　reservoirs　can　potentially　be　developed　more　efficiently　with　the　use　of　liquid　nitrogen　(LN2)　fracturing.　In　order　to　evaluate　the　effects　of　LN2　freeze-thaw　on　the　physical　and　mechanical　properties,　as　well　as　the　failure　behavior　of　sandstone,　the　research　involved　conducting　a　range　of　experiments　and　numerical　simulations　on　sandstone　samples　subjected　to　various　LN2　treatment　conditions.　The　results　indicated　that　the　freeze-thaw　process　had　a　detrimental　effect　on　the　physical　and　mechanical　properties　of　the　sandstone,　leading　to　varied　degrees　of　weakening.　The　reduction　percentages　of　tensile　strength　and　fracture　toughness,　which　are　two　key　indicators,　were　found　to　be　14　%　and　21.4　%　respectively.　Furthermore,　there　were　the　bigger　degree　of　volume　fracture,　multiple　branching　and　tortuous　macroscopic　cracks　and　macro　fracture　surface　with　larger　roughness　(increased　by15　%)　in　the　freeze-thaw　sandstone　after　destruction.　The　physical　mechanical　properties　of　the　freezing　sandstone　were　significantly　enhanced,　but　the　complexity　of　the　tensile　failure　path　increased.　Numerical　simulations　indicate　that　a　large　temperature　gradient　leads　to　the　formation　of　damage　zones　within　the　sandstone　matrix,　and　microscopic　observations　show　a　significant　increase　in　the　length　and　width　of　microcracks　within　the　matrix.　This　indicates　that　the　low　temperature　of　LN2　fully　releases　the　damage　potential　of　initial　defects　in　sandstone,　the　damage　area　participates　in　the　formation　of　crack　propagation　paths　and　increases　the　randomness　of　path　direction　selection,　which　increases　the　degree　of　sandstone　volume　fracture.　The　research　results　are　anticipated　to　offer　a　scientific　foundation　and　data　references　for　the　efficient　development　of　tight　sandstone　gas　resources.