This work was designed as a synthetic analysis of naturalistic elements in Croatian prose from the late nineteenth to early twentieth century. In it will be analyzed the naturalistic elements of three novels and one story: the novels Olga i Lina, and Začuđeni svatovi by Eugen Kumičić, Tito Dorčić by Vjenceslav Novak, and story Tena by Josip Kozarac. The purpose of this paper is to show the extent to which the authors mentioned in their works relied on the idea invoked by French novelist Émile Zola. To give a clearer picture of the idea of naturalism, the main features of naturalistic poetics will be briefly highlighted. After that, there will be talk of the controversy of Croatian writers which developed after the naturalist idea began to spread among writers. From the aforementioned works, the elements that in their nature bear the characteristics of natural poetics will be distinguished. In the end, a conclusion will be drawn on how successful the authors were in their intentions and how true they were to the naturalistic idea. In addition to the aforementioned sources, supplementary literature will be used in order to present the naturalistic poetics and controversy surrounding naturalism in Croatian literature. Zola's „Eksperimentalni roman“, which is found in Povijest književnih teorija gathered under the editorial board of Vera Čičin-Šain, and the foreword of the secon edition of the novel Thérèse Raquin, which is considered to be one of the manifestations of naturalism. To review the controversy of naturalism, will be a book of critics by Jakša Čedomil O književnosti and Pregled novije hrvatske književnosti by Miroslav Šicel, and used articles are: Josip Pasarić's essay „Hoćemo li naturalizmu?“, which is in a collection of criticism under the editorial board Krsto Špoljar, and the article by Miroslav Šicel „Polemike o realizmu i naturalizmu u hrvatskoj književnosti“.