AbstractThe intrinsic helical π‐conjugated skeleton makes helicenes highly promising for circularly polarized electroluminescence (CPEL). Generally, carbon helicenes undergo low external quantum efficiency (EQE), while the incorporation of a multi‐resonance thermally activated delayed fluorescence (MR‐TADF) BN structure has led to an improvement. However, the reported B,N‐embedded helicenes all show low electroluminescence dissymmetry factors (gEL), typically around 1×10−3. Therefore, the development of B,N‐embedded helicenes with both a high EQE and gEL value is crucial for achieving highly efficient CPEL. Herein, a facile approach to synthesize B,N‐embedded hetero[9]helicenes, BN[9]H, is presented. BN[9]H shows a bright photoluminescence with a maximum at 578 nm with a high luminescence dissymmetry factor (|glum|) up to 5.8×10−3, attributed to its inherited MR‐TADF property and intrinsic helical skeleton. Furthermore, circularly polarized OLED devices incorporating BN[9]H as an emitter show a maximum EQE of 35.5 %, a small full width at half‐maximum of 48 nm, and, more importantly, a high |gEL| value of 6.2×10−3. The Q‐factor (|EQE×gEL|) of CP‐OLEDs is determined to be 2.2×10−3, which is the highest among helicene analogues. This work provides a new approach for the synthesis of higher helicenes and paves a new way for the construction of highly efficient CPEL materials.