In the field of marketing in culture, it is important to represent and popularize cultural and artistic achievements and to encourage acontact between people and art, works of art, and cultural institutions. It is therefore important to explore "distance of producers and consumers", and market access to culture imposes a requirement to encourage consumption due to higher economic returns as well as institutions whose products are marketable (exhibition, performance, etc.). Unconventional marketing is facing a "fertile ground" for implementation because the cultural institutions in Croatia should have a creative, low-cost and interesting promotion, while also being more aware that kind of promotion. Every cultural institution has its own mission and vision. The task of marketing in culture should be that as large as possible a number of people should familiarize themselves with a fore mentioned mission and vision. The purpose of this paper is to explore the attitudes of employees in Croatian cultural institutions (in this case theaters, museum and galleries are explored) about unconventional marketing. An intention of this dissertation author was to obtain a whole picture of the potential and actual use of unconventional marketing. This was achieved through the results of a survey about the attitudes of employees in cultural institutions concerning unconventional marketing and the ways to use conventional and unconventional marketing in cultural institutions. This thesis starts with the problems, objectives, purpose and research subject, scientific contribution and with the explanation of structure of the work. Further terms such as culture and institutions, meaning, establishment and operation of the theater, museums and galleries activities are explained. Along with theater, museums, and galleries, activities in the dissertation also define other cultural institutions classified by the Statistical Annual of the Republic of Croatia. They are libraries, archives, motion picture theatres, music institutions and representatives of polyvalent institutions (elementary schools, community cultural center, cultural centers, cultural enterprises, city cultural centers, etc.). After that, the thesis presents several important definitions of marketing and its history, so the reader may easier understand marketing in the culture, and a relationship between cultural institutions and marketing more easily. Most importantly, subsequent to an introduction to marketing in theaters, museums and galleries are presented. After the introduction of marketing and marketing in culture, the 6 author of the thesis describes the history and review of guerrilla marketing and explains today's most relevant unconventional marketing methods such as the Trojan marketing (not yet existing in the Croatian literature), electronic marketing, "word of mouth" and neuro-marketing. The fifth chapter, "Unconventional marketing in cultural institutions", created by the author's practical experience, describes the case studies that occurred during the writing of the dissertation whereby the author has devised a way to connect the visitors and cultural institutions by an unconventional communication. The chapter also demonstrates one of the most successful implementations of unconventional marketing in cultural institutions around the world. Subsequent to a theoretical discussion and analysis of previous research and cases, in the order for analyzing comes empirical research description which are described the characteristics of the sample and questionnaire. The survey sample implies theaters, museums, and galleries in Croatia, whereby the main part of the empirical research in this paper is a quantitative method. In order to obtain the required informations for the thesis research, the author has decided to carry out an online questionnaire. Research results are divided in the following four parts: a) results of univariate statistical analysis of cultural institutions using marketing in business; b) identification of cultural institutions using unconventional marketing; c) differences between cultural institutions using unconventional marketing; d) analysis of cultural institutions in accordance with the access and use of unconventional marketing. Following the empirical research, the author of the dissertation conclusively explains the relation between unconventional marketing and cultural institutions, and recommendations for a future research.