Cooperative communications have received an increasing attention in the last few years due to the spread of wireless devices. While multi-antenna systems can improve the system performance greatly, it is difficult to implement antenna arrays on hand-held devices due to size, cost and hardware limitation. Cooperation allows the users to share their single-antenna devices to create a virtual multi-antenna system that benefits from the transmit diversity. On the other hand, low density parity check (LDPC) code is a class of linear block codes that can theoretically approach the Shannon limit. In this work, we propose an automatic-repeat-request (ARQ)-based LDPC coded cooperative system that provides an improvement in both error rate and throughput.