In　order　to　study　the　bending　resistance　and　damage　evolution　of　precast-beam　with　engineered　cementitious　composites　(hereafter　known　as　ECC)　floor,　11　specimens　were　designed　and　manufactured.　The　bending　behaviors　of　specimens　with　different　reinforcement　ratios,　thicknesses　of　ECC　floor　and　connecting　types　of　steel　bars　were　studied　through　bending　test.　Fractal　theory　was　applied　to　study　the　relationship　between　the　fractal　dimension　and　the　mid-span　displacement,　ductility,　first-order　frequency,　dynamic　stiffness　and　static　stiffness　degradation　of　the　specimen.　Damage　evolution　law　of　dynamic　stiffness　and　static　stiffness　degradation　was　put　forward.　The　results　show　that　the　ductility,　yield　force,　yield　displacement　and　fractal　dimension　at　failure　point　of　beams　with　precast　ECC　layers　improve　compared　with　ordinary　reinforced　concrete　beams.The　ductility　and　failure　factor　increase　with　the　fractal　dimension;　the　bending　stiffness　and　first-order　frequency　decrease　with　the　increasing　of　the　fractal　dimension.　Fractal　theory　provides　a　new　method　to　estimate　the　damage　evolution　of　the　specimen　and　thus　can　be　applied　in　engineering　practice.　©　2020,　Editorial　Office　of　Journal　of　Building　Structures.　All　right　reserved.