The tip-of-the-tongue (TOT) phenomenon is an intense feeling that the sought-after information is known and that the information will pop into mind at any moment. Until now, researches had proposed 5 theories to explain the TOT’s produce. These are Partial Activation Theory, Transmission Deficit Hypothesis, Blocker Hypothesis, Metacognitive Control Theory, and Quantitative Neural Network Model. But most of the results from cross-linguistic support the first two theories. Compared with the researches about the tip-of-tongue of bilinguals in foreign countries, due to the complexity of Chinese language combined with its difficult operation, there always lack of diglossia TOT studies in China. According to cross-linguistic interference theory, bilinguals are in bad situation in language production or lexical process. Considering that diglossia and bilingual both have similarity and difference, then, this “bad situation in lexical process” whether happen on diglossias? How the familiarity of dialect can influence the TOT? And, what’s the mechanism of this diglossias TOT? 100 subjects participated in this research. All of subjects were native speaker of Cantonese, and were chosen randomly from a high middle school in Guangzhou suburbs. 56 of them can speak mandarin fluently, while another 44 can speak Cantonese but non-smoothly. This research contained 3 experiments, using picture-naming paradigm and E-Prime programming technology. In experiment, subject and experimenter were in the form of one-to-one and experimenter recorded participant’s response (including 5 dependent variables as GOT, Positive TOT, Negative TOT, Don’t Know, andj Post Don’t Know) in the whole course. At last, used mix design variance analysis to process the data of PTOT rates and GOT rates. In experiment 1, compared the TOT rates of two kinds of participants when using different languages, and the results showed a significant higher TOT rates and lower GOT rates for these participants who unfamiliar with Mandarin. This contributed to the partial activation theory preliminary. In experiment 2, adding auditory priming information (the family name of these stars, including 3 types: Cantonese, Mandarin, and irrelevant) as an independent variable, exploring the difference of GOTs and TOTs when naming in different language and in different priming condition. The results showed that GOT rates was higher in the condition of Mandarin and Cantonese priming than in irrelative priming, and the TOT rates was significant higher when priming and naming both in Mandarin, but in Cantonese priming, TOT rates caused by two naming was non-significant. What’s more, in contrast with exp.1, Mandarin familiar speakers experienced more TOTs than these who unfamiliar. To sum up, language familiarity affect language production. The more the language familiarity is, the easier to naming. This effect can be explained by the differences of lexical representation and language dependent effects. Besides, it states that the mechanism of diglossia is Partially Activation Theory and can be explained by nodes structure theory (NST). In exp2, the TOT rate was significant higher when priming and naming both in Mandarin. As explained by NST, it confirms the Partially Activation Theory again.