A series of vinyl copolymers (PVKST12–PVKST91) and homoploymer PVST containing pendant hole-transporting 4-(4-oxystyryl)triphenylamine (12–100mol%) and carbazole chromophores were synthesized by radical copolymerization and employed as host for Ir(ppy) 3 phosphor to tune emission color. They were characterized using the 1 H NMR, FT-IR, absorption and photoluminescence spectra, elemental analysis, GPC, cyclic voltammetric and thermal analysis (DSC, TGA). Their weight-average molecular weights (M w ) and decomposition temperatures (T d ) were 1.46–5.68×10 4 and 356–399°C, respectively. The HOMO levels of PVKST12–PVKST91 and PVST, estimated from the onset oxidation potentials in cyclic voltammograms, were −5.40 to −5.14eV, which are much higher than −5.8eV of the conventional host poly(9-vinylcarbazole) (PVK) owing to high hole-affinity of the 4-(4-oxystyryl)triphenylamine groups. Therefore, copolymers PVKST are effective in reducing hole-injection barrier between the PEDOT:PSS and emitting layer. Electroluminescent devices [ITO/PEDOT:PSS/PVKST:Ir(ppy) 3 :PBD/BCP/Ca/Al] using the hole-transporting PVKST as host were fabricated to tune the emission color. Their EL spectra showed a major emission at 515nm and a minor peak at 435nm attributed to Ir(ppy) 3 and 4-(4-oxystyryl)triphenylamine, respectively. The C.I.E. 1931 coordinates shift from (0.29, 0.61) for PVK to (0.33, 0.42) for PVST with an increase in 4-(4-oxystyryl)triphenylamine content.