This paper presents an experimental evaluation and analysis of the effects of phonological relevance between the training and test utterances in speaker verification, while the test utterances in short durations of 3, 5 and 10 seconds are used in the experiments. We quantify the phonological relevance as the occurrence ratio of the subword units of a test utterance in the training utterance. It is found that a higher phonological relevance can make a large reduction of the miss detection error rate without increasing much in the false acceptance in text-independent speaker verification.