According to experts in rhetoric, Interrogation refers to asking about a thing which is unknown to the speaker and aims at knowing something; they mention, however, that these statements deviate from their real purposes sometimes and refer to some other secondary meanings. Writers have mentioned more or less different secondary purposes mainly based on the Quran. More recent writers have also provided some examples of more secondary rhetorical purposes. Persian language is among those languages in which different meanings can be inferred from statements. This paper intends to survey the secondary purposes of interrogative statements in Saadi's Ghazals. In addition to improving rhetorical knowledge of secondary purposes, this paper shows that secondary purposes of interrogative statements are not limited to what were introduced by old and modern rhetorical writings, since special verbal structures were used by Saadi to indicate minute rhetorical intentions. His Ghazals are the best sources to identify secondary purposes of interrogative statements in Persian. The survey is a theoretical research based on library studies with descriptive-analytic method and the results have been analyzed contextually. Statistical society is 714 and the sample size is 238 based on Krejcie-Morgan's formula arranged in random sampling. The results show that Saadi paid attention to 45 secondary purposes in interrogations and used different meanings and purposes in one statement simultaneously.