XXIX. century is the period through which the Ottoman State radically went some military, admnistrative, social, cultural and economic changes. Especially, when the Tanzimat was declared in 1839, non-muslims were granted some rights such as the guarantee of life, honor and property of the subjects, the equal status between the Muslims and the non-muslims and the equality before the law. Thus, in the course of time following the Tanzimat and the Islahat Edicts, some changes took place in the social, political, economic lives of both Muslims and non-muslims. Even though some had the Muslim identity, they practiced deception and retained their old faiths and rites. Paralel to the emergence of some political, social and edonomic changes peculiar to the XIX. century, when they were granted some rights, they felt more secure under the wings of the Western powers. Subsequently, some of them declared that they are not Muslims and this time they wanted to benefit from the advantages of being a Chrtistian. As in the case of Kurumlis living in the north of Gumushan in the Trabzon (Trebizon) Povince, some goups officially registered as Muslims openly started to declare that they are not Muslims and demanded to convert to their own faith especially following the Islahat Edict (1856). The purpose of this study is to use the accounts of some Western travelers and researchers who came to Trabzon in the XIX. century and analyze, question and evaluate their opinions about the existence of the Crypto-Christians living in Trabzon and in its vicinity.