Manufactured　sand　(MS)　is　a　promising　alternative　aggregate　to　quartz　sand　(QS)　in　ultra-high-performance　concrete　(UHPC)　in　the　preparation　of　ultra-high-performance　manufactured　sand　concrete　(UHPMC),　which　possesses　the　characteristics　of　high　strength,　low　cost,　and　environmental　friendliness.　In　this　study,　the　effects　of　variable　compositional　characteristics　including　the　water-binder　ratio,　the　stone　powder　(SP)　content,　and　the　MS　replacement　ratio　on　the　mechanical　and　flexural　strength　of　UHPMC　were　compared　and　analyzed　based　on　response　surface　methodology　(RSM).　Meanwhile,　the　damage　characteristics　of　UHPMC　during　compressive　and　flexural　stress　were　monitored　and　evaluated　using　acoustic　emission　(AE)　technology.　The　results　reveal　that　the　compressive　and　flexural　strengths　of　UHPMC　are　both　negatively　correlated　with　the　water-binder　ratio,　while　they　are　positively　correlated　with　the　MS　replacement　rate.　They　tend　to　firstly　increase　and　subsequently　decrease　with　the　increase　in　the　stone　powder　content.　In　the　load-displacement　curve　of　concrete　with　a　high　MS　replacement　ratio　and　a　low　water-binder　ratio,　the　slope　in　the　elastic　stage　is　steeper,　the　stiffness　is　higher,　and　the　bending　toughness　and　ductility　are　also　better.　The　specimens　with　a　10%　to　0%　stone　powder　content　present　a　steeper　elastic　phase　slope,　a　slightly　higher　stiffness,　and　superior　ductility.　The　specimens　with　a　low　MS　replacement　ratio　and　a　high　water-binder　ratio　display　earlier　cracking　and　weaker　resistance,　and　the　destruction　process　is　complex　and　very　unstable.　The　damage　mode　analysis　based　on　RA-AF　shows　that　an　increase　in　the　MS　replacement　ratio　and　a　decrease　in　the　water-binder　ratio　can　both　reduce　the　tensile　cracking　of　UHPMC　specimens　under　a　four-point　bending　test.　Although　10%　stone　powder　can　marginally　slow　down　crack　growth,　the　failure　mode　is　not　significantly　affected.