High-efficiency blue fluorescent organic light emitting devices (OLEDs) with do uble emission layers (DELs) have been demonstrated with structure of ITO/4,4′,4＂-T ris (N-3- methylphenyl-N-phenyl-amino) triphenylamine (m-MTDATA)(40nm)/ N,N′-Bis(naphthalen-1-yl)-N,N′-bis(phenyl)benzidine(NPB)/(10nm)/9,0-Di(naphth-2-yl)anthra cene(ADN):N-(4-((E))-2-(6-((E)-4-(diphenylamino)styryl)nap hthalen -2-yl) vinyl)phenyl)-N-phenylbenzenamine(N-BDAVBi)(15nm)/4,4′-Bis(2,2-diphenyl-ethen -1-yl) biphenyl(DPVBi):N-BDAVBi(15nm)/2,2′,2＂-(1,3,5-Benzine triyl)-tris(1-phenyl-1-H-benzimidazole(TPBI)(30nm)/LiF(0.6nm)/Al.N- BDAVBi as blue emitting dopant is doped into ADN host and DPVBi host simultaneou sly to form DELs.The DEL devices show significant improved efficiency compared w ith the conventional devices with a single emitting layer (SEL).The maximum curr ent efficiency of 8.13cd/A with a Commission International deL′Eclairage (CIE) coordinate of (0.178,0.302) at current density of 18.81mA/cm^2is obtained in DEL device,which is about 140% and 80% g reater than that of the devices with ADN:N-BDAVBi and DPVBi:N-BDAVBi as emission layer,respectively.The im provement of the current efficiency is attributed to the reduced accumulation of charge carriers at the interfaces,the expansion of the exciton generation region,and the efficient energy transfer from host to dopant.The maximum luminance of 20620cd/m^2has been acieved at 14V in DEL device.The CIE chromaticity coordi nate of DEL device changes only from (0.181,0.308) to (0.172,0.292) as the l umin ance increases from 1000cd/m^2to 5000cd/m²．