Abstract: Trellis coded modulation (TCM) combines the convolutional coding with PSK or QAM modulation to provide large coding gain in a power-limited o rbandwidth-limited. In this paper is presented a combined punctured convolutional coding and MPSK modulation scheme. Best punctured convolutional codes that have the maximum Euclidean distance are searched for rate 2/3. The results show that punctured convolutional codes with the maximum free distance cannot give the maximum coding gain when compared with an encoded system for the same rate;the good codes derived can have the same coding gain as the Ungerboeck's codes. With the punctired structure the decoding complexity can be significantly simplified.