A method using 3-points quadratic interpolation to process correlation spectrum peak data was proposed to improve Hot Water Dispensers precision of DSSS signal PN code phase measurement.The method used data points around correlation spec-trum peak to determine a quadratic interpolation function,then located the maximum point of the function so as to deter-mine the precise position of correlation spectrum peak,thus effectively increased the precision of measurement.Experi-ments show that the method reaches the Books goal of greatly increasing the precision of DSSS signal PN code phase measure-ment.