On　the　basis　of　finite-difference　time-domain　simulations,　a　novel　strategy　is　developed　to　prepare　highly　efficient　bis(2-(2＇-benzothienyl)　pyridinato-N,　C-3＇)　iridium　(BTP)　and　AuNP　polyiohexol　composite　nanoparticles　(BAPI　NPs)　as　dual-modal　phosphorescence/computed　tomography　(CT)　bioprobes.　In　these　bioprobes,　BTP　and　AuNPs　are　both　encapsulated　with　polyiohexol　NPs.　All　bioprobe　components　perform　two　functions　here:　AuNPs　could　be　used　as　both　a　CT　contrast　agent　and　a　phosphorescence　enhancement　reagent　of　BTP　with　a　metal-enhancement　fluorescence　effect.　The　results　showed　that　BAPI　NPs　were　almost　spherical　in　shape,　with　an　average　size　of　50.36　+/-　3.8　nm　and　a　higher　total　contrast　agent　loading　ratio　of　69.4%.　Fourier　transform　infrared　spectra　confirmed　that　AuNPs　and　BTP　are　encapsulated　in　BAPI　NPs.　It　is　shown　that　they　have　lower　toxicity　for　tissues　and　cells,　their　phosphorescence　intensities　are　8.27-fold　that　of　BTP　polyiohexol　NPs　(BPI　NPs),　the　average　phosphorescence　intensity　of　the　BAPI　NPs　was　1.46　times　higher　than　that　of　BPI　NPs　and　5.85　times　that　of　BTP　alone　in　vivo.　Improved　CT　imaging　is　obtained　at　a　low　dose　of　polyiohexol　in　vivo.　These　bioprobes　not　only　have　highly　efficient　and　excellent　dual-modal　imaging,　but　they　also　save　the　use　of　various　materials,　indicating　that　these　bioprobes　are　the　potential　dual-modal　probes　of　the　future.