中文摘要：

音节时长的研究是韵律模型和语音合成系统的基础，本文基于词汇层面，随机挑选了单音节词、双音节词、三音节词、四音节词（成语）各200个，录制了1男1女藏语拉萨话发音人的语音，提取有效时长。研究了男女发音人不同长度词汇的时长分布，并对不同长度词汇的音节平均时长进行比较。结果表明：1）男女声的词汇时长总体分布比较集中；2）随着词汇长度的增加，音节平均时长逐渐变小，减小幅度成递减趋势；3）整体上来看，女声时长要大于男声时长。

英文摘要：

The study of Syllable time-period is the basis of prosody model and speech synthesis system. Based on the floor of vocabulary, the speech of one man and one woman are chosen and 200 one-syllable words, bi-syllable words, three-syllable words and four-syllable words in Tibetan speech of Lassa. The material is chosen by accident. Then the meaningful time-period of syllable is gotten. The paper does research on the range of time-period of man and woman in vocabularies with different time-period and does comparison on the average time-period in vocabularies with different time-period. The result shows that： 1） The population distribution of syllable time-period of male and female voice is comparatively concentrated. 2） As the vocabulary length adds, the average time-period of syllable becomes shorter; 3） From the who/e, the time-period of woman is longer than man＇ s.