Shellfish are an important part of the diet and a source of income for many residents of the Republic of Croatia due to the proximity of the Adriatic Sea and the traditional presence in the culture of the society in this region. The main objective of this study was to examine the relationship between knowledge about shellfish, production technology, nutritional and toxicological characteristics with age, gender, level of education and eating habits of shellfish consumption in a sample of adults from the general population living in Croatia. A survey questionnaire was used to conduct the research. The questions within the questionnaire were divided into those that found out the socio-demographic characteristics of the participants in the research and their eating habits related to shellfish consumption, and those that examined the participants' theoretical knowledge about shellfish. The research showed that the presence of shellfish in the diet in the Republic of Croatia is relatively small. People over the age of 40 consume shellfish more often, but the presence of shellfish in the diet does not affect the level of knowledge about shellfish. The level of knowledge about the toxicities and nutritional value of shellfish is higher than the level of knowledge about the technology of their cultivation. Geographical factors have a greater impact on the level of knowledge about shellfish than sociodemographic factors and eating habits. These results potentially reflect the need to educate the general population about shellfish. Further research should investigate the relationship between the level of knowledge about shellfish toxicity and previous experiences on a representative sample with a larger number of subjects.