Oral history (research method/technique and discipline of the history so-called „ordinary people”, who were so far beyond the interest of historians or who did not produce traditional sources to get to know their past) has made the memory a historical source. However for this to become, the interviews with people (conducted according to specific rules, for example asking open-ended question, what encourage people to say what they would like to say) who participated in or observed past events must be preserved as an aural record or in written form in archives or libraries. The oral history can lead not only to the new facts or new interpretations of the past, but also can be used in research of history of mentalities. Memoires are neither a pure reflection of the events of the past, or distorted version of a particular experience, but his “functional reduction”, the “functional” in this sense that it matched the number of individual factors. People remember by organizing memories in the frame of their experiences, create important for them, the image of past events. As a result, the oral history was accuses of lack of credibility, deforming the facts and dependence on the circumstances of the recall. Alessandro Portelli replied to this accusation, that the biggest advantage of oral history is not discover the new events of the past, but the fact that oral history enters into the field of imagination, symbolism, desires, perceptions and interpretations. As a result of such an approach “memory errors” and “false statements”, which is their due, they have research value. Focusing not only in the facts, as postulated among others Alessandro Portelli, could lead to the realm of mentality, as well as to the social, cultural and material factors that influence it. Analysis transcripts of interview, conducted according to certain rules, can provide to the interesting information about how people understand processes and situations. This can lead to the sphere of values, attitudes and beliefs. For the study of mentalities, interested in reconstruction of the collective concept of reality, myths and imagination, recognized by the group and all of society, or which have an impact on them, oral history is a valuable source.