Multiple-Input Multiple-Output (MIMO) spatial multiplexing is a promising technique to increase the channel capacity without increasing bandwidth. One of the key to successful application of this technique is in receiver design. Recently, a low complexity receiver algorithm, based on asymmetrical poly-diagonalization and trellis decoding, is investigated. It can provide tradeoff between performance and complexity. In this paper, we provide a new iterative receiver scheme for asymmetrical poly-diagonalization and trellis decoding. The performance of asymmetrical poly-diagonalization and trellis decoding will upgrade with our proposed iterative receiver scheme.