The　energy　dissipation　and　stress-strain　characteristics,　and　characteristic　stresses,　namely　the　crack　initiation　σci,　dilatancy　σcd,　and　peak　σf　stresses,　of　polypropylene　fiber-reinforced　recycled　concrete　under　uniaxial　compression　were　studied.　According　to　the　research　results,　the　crack　initiation　and　peak　stresses　of　the　specimen　with　single-blend　polypropylene　coarse　fiber　(No.　3)　and　the　specimens　with　mixed-blend　coarse　and　fine　polypropylene　fibers　(No.　4　and　No.　5)　are　higher　than　those　of　the　specimen　with　single-blend　fine　fiber　and　plain　concrete.　The　analysis　of　the　energy　characteristics　and　failure　mechanism　of　polypropylene　fiber-reinforced　recycled　concrete　during　loading　based　on　the　principle　of　energy　conservation　showed　that　the　total　strain　energy,　elastic　strain　energy,　and　dissipation　energy　absorbed　per　unit　volume　increase　with　the　blending　of　polypropylene　fiber.　The　strain　energy　and　elastic　strain　energy　of　coarse　aggregates　with　a　5-10　to　10-20　mm　coarse　aggregate　size　ratios　of　5:5　are　higher　than　those　of　4:6　and　6:4.　It　was　found　that　the　continuous　blending　of　polypropylene　fiber　increases　the　elastic　strain　energy,　causing　the　point　at　which　the　dissipation　energy　exceeds　the　elastic　strain　energy　move　further　and　further　back.　The　position　where　the　dissipation　energy　exceeds　the　elastic　strain　energy　can　be　used　to　evaluate　the　blending　effect　of　polypropylene　fiber.　The　further　back　the　position,　the　better　the　blending　effect.　©　Springer　Science+Business　Media,　LLC,　part　of　Springer　Nature　2024.