The invention discloses a parallel encoding realization circuit and an encoding method based on CABAC (Context-based Adaptive Binary Arithmetic Coding) in H.264/AVC (Advanced Video Coding). The parallel encoding realization circuit comprises a binary engine, a context model engine, a parallel normalization engine and an RBSP (Remote Batch Station Processor) code stream generation engine, wherein the binary engine is used for executing a parallel normalization operation; the context model engine is used for executing context read and updating operation of two bits per period; the parallel normalization engine is used for executing the normalization operation of two bits per period; and the RBSP is used for generating an RBSP output code stream. The binary engine and the context model engine are connected in a three-writing, two-reading and first-in, first-out queue; and the parallel normalization engine and the RBSP code stream generation engine are connected in a two-writing, one-reading and first-in, first-out queue. The invention ensures that processing speeds of the binary engine, the normalization engine and the RBSP code stream generation engine are matched, avoids productionline stagnancy and solves the problems of unbalanced throughput rates among various levels of processing engines and calculation bottleneck initiated by correlation of a coding interval, coding lowerlimit normalization and a code stream production process.