Comprehensive Summary By simplifying the π‐bridge unit, a nonfused ring electron acceptor (NFREA) BM‐2F was designed and synthesized with several high‐yield steps. The specific molecular structure features of BM‐2F are planar molecular backbone and out‐of‐plane side chain, which is favorable for charge transport and can suppress the over‐aggregation. BM‐2F based neat and blend films display obvious face‐on molecular orientation. Specially, D18:BM‐2F based blend film can form good bicontinuous interpenetrating network. More excitingly, a power conversion efficiency of 16.15% was achieved with D18:BM‐2F based photovoltaic devices, which is the highest one based on NFREAs. Our researches manifest that NFREA is a promising direction for low‐cost and high‐performance organic solar cells. We designed a novel nonfused ring electron acceptor (BM‐2F), which can be obtained by four‐step high‐yield synthetic steps and is of 3D molecular structure. With D18 as polymer donor, the devices can afford a champion power conversion efficiency of 16.15% and display high FOM value, demonstrating great potential for future commercial application.