A new block-delayed partitioned Viterbi algorithm (BD-PVA) receiver for the MIMO frequency-selective fading channel is proposed. The classic PVA has a trellis detector for each transmit antenna and feeds back tentative decisions between these trellis detectors. The proposed algorithm uses more reliable temporary decisions in the feedback loop instead of the tentative decisions, thus resulting in an improved BER performance. MIMO systems with higher number of antennas exhibit a more remarkable BER performance improvement since they rely more on the feedback between the trellis detectors.