A method for the estimation of threshold in utterance verification is presented here. In a speech recognition system with utterance verification module, the statistics of utterance verification scores are stored in advance before using the corresponding verification models and training corpus. The distribution of utterance verification scores with respect to recognition targets will be depicted using these statistics, and the threshold will be predicted for the verification module. By using this method, both the online adjustment of the threshold and the analysis of the collected data with respect to recognition targets are no longer needed. From the experimental results, the prediction error is always less than 6% under different noise environment and false rejection rate.