The　present　study　investigates　the　fatigue　behavior　of　granite　and　red　sandstone　under　coupled　static　and　cyclic　loading.　Experimental　results　reveals　a　three-stage　evolution　trend　for　the　deformation　modulus,　Young＇s　modulus,　peak　strain,　residual　strain,　dissipated　energy　as　a　function　of　the　absolute　cycle.　Acoustic　emission　(AE)　rate　also　exhibits　a　three-phase　stage,　including　the　initial　phase,　uniform　velocity　phase,　and　accelerated　phase.　To　explain　the　mechanical　responses　and　fracture　mechanisms　related　to　rock　fatigue,　this　study　built　a　micromechanics-based　damage　model　that　adopts　a　modified　Paris　law　and　considers　both　the　effect　of　static　stress　and　stress　amplitude.　The　theoretical　model　successfully　reflects　the　effect　of　static　loading　history　and　reproduces　the　three-stage　evolution　of　residual　strain　during　rock　fatigue.　The　SIF　deduced　by　the　theoretical　model　exhibits　a　distinct　behavior:　it　initially　decreases　during　the　first　few　cycles,　stabilizes　at　a　lower　value,　and　subsequently　undergoes　a　significant　increase　as　it　approaches　the　final　cycles.　The　internal　cause　behind　the　three-stage　evolution　of　crack　growth　rate,　AE　rate,　and　mechanical　properties　is　attributed　to　subcritical　crack　growth　during　cyclic　loading.　Finally,　the　theoretical　model　successfully　characterizes　the　effect　of　static　stress　and　stress　amplitude　of　cyclic　loads　on　fatigue　damage　evolution.