A new technique for representing and decoding of nonlinear block codes has been investigated based on the tree-trellis construction method. Such a technique is applied to the EFMPlus recording code used in the digital versatile disc (DVD). By employing the tree-trellis construction technique, a reduction in the overall complexity of the decoding process can be achieved. Simulation test results have also shown that a performance improvement has been attained for the new technique when compared to the conventional decoding method.