Abstract: MIMO system offers substantial gain in through put and link reliability in wireless systems. Precoding in MIMO plays a vital role in mitigating fading and co-channel interference effects in time-variant channels. Despite of these advantages, the wireless system is more prone to packet errors and loss due to channel distortions, noise or fading. This in turn invokes the necessity of retransmission in MIMO. A codebook based precoding approach is used in retransmission systems in which instead of using a single codebook, a new codebook is designed for each retransmission using Lloyd algorithm which minimizes the average distortion. This approach combines the effect of precoding and retransmission in MIMO thereby providing high sum rate and BER.