This paper presents an encoder core architecture for Context-Based Adaptive Binary Arithmetic Coding (CABAC) in H.264/AVC main profile. The throughput of CABAC encoder is usually limited due to i) bit-wise processing, ii) complicated data dependency, and iii) variant iteration times for each binary symbol. This paper adopts dynamic pipeline scheme to improve the performance of CABAC encoder. The characteristics of CABAC algorithm are utilized to reduce pipeline latency. Meanwhile, pipeline bypass scheme is applied to eliminate the possible memory conflict Proposed encoder core is implemented under ROHM 0.35μm technology. Results show that the equivalent gate counts is 4.57k when the maximum frequency is 150MHz. It is estimated that the proposed CABAC encoding core can process the input binary symbol at a bit-rate of 80Mb/s.