The next generation wireless local area networks (WLANs) with enhanced throughput performance have attracted significant amounts of attention in recent years. Based on the IEEE 802.11n standard, frame aggregation is considered one of the major factors to improve the system performance of WLANs from the medium access control perspective. In order to fulfill the requirements of the high throughput performance, feasible design of automatic repeat request (ARQ) mechanisms is considered important for providing reliable data transmission. In this paper, an aggregated selective repeat ARQ (ASR-ARQ) algorithm is proposed, which incorporate the conventional selective repeat ARQ scheme with the consideration of frame aggregation. A novel analytical model based on the signal flow graph is established in order to realize the behaviors of ASR-ARQ algorithm. Simulations are also conducted to validate the effectiveness of proposed ASR-ARQ mechanism.