In　order　to　study　the　dynamic　characteristics　of　three-span　bonded　prestressed　continuous　beam,　the　paper　established　the　analysis　model　of　prestressed　tendon　layout　based　on　the　Bernoulli-Euler　beam　theory.　Through　establishing　the　relationship　between　prestress　force　and　displacement　and　taking　the　continuous　beam　as　the　multiple　single　beams　satisfying　with　the　moment,　angle　and　displacement　boundary　conditions,　the　vibration　equation　of　beam　using　piecewise　simultaneous　method　was　established　and　the　analytical　solution　of　the　frequency　equation　was　obtained.　Then　the　frequency　equation　was　solved　to　get　natural　frequency.　Taking　a　three-span　bonded　prestressed　continuous　beam　as　example,　the　natural　frequencies　obtained　by　this　method　was　compared　with　those　calculated　by　finite　element　method　(FEM)　and　actual　bridge　test.　The　results　show　that　relative　error　of　fundamental　frequency　is　only　0.6%　and　the　maximum　error　of　the　first　four　frequencies　is　within　3%　when　this　method　and　finite　element　method　are　adopted.　The　relative　error　of　fundamental　frequency　is　-1.18%　and　the　average　error　of　the　first　three　frequencies　is　within　3%　when　this　method　and　actual　bridge　test　are　adopted.　It　is　found　the　results　calculated　by　the　formulas　are　in　good　agreement　with　the　results　of　FEM　and　actual　bridge　tests.　Thus　by　adopting　this　method,　the　dynamic　parameters　such　as　natural　frequencies　of　three-span　bonded　prestressed　continuous　beams　can　be　obtained　accurately.　©,　2015,　Editorial　Department　of　Journal　of　Chang＇an　University　(Natural　Science　Edition).　All　right　reserved.