In this paper, we propose a new method of phoneme segmentation using MLP(multi-layer perceptron), The structure of the proposed segmenter consists of three parts: preprocessor, MLP-based phoneme segmenter, and postprocessor. The preprocessor utilizes a sequence of 44 order feature parameters for each frame of speech,based on the acoustic-phonetic knowledge, The MLP has one hidden layer and an output layer, The feature parameters for four consecutive inter-frame features (176 parameters) are served as input data. The output value decides whether the current frame is a phoneme boundary or not. In postprocessing, wt decide the positions of phoneme boundaries using the output of the MLP, We obtained 84 % for 5 msec-accuracy and 87 % for 15 msec-accuracy with an insertion rate of 9 % for open test, By adjusting the threshold value of the MLP output, wt achieved higher accuracy, When we decreased the threshold by 0.4, we obtained 5 msec-accuracy of 92 % with insertion rare of 3.4 % for the insertions that are more than IS mse! apart from phoneme boundaries.