The article aims to define the role of the ethnocentric attitude of purchasers in their integration with offerors through prosumption. It is of a theoretical and empirical nature. For the theoretical aspect, the literature on marketing, consumer behaviour, etc., was cognitively and critically analysed. For the empirical aspect, a questionnaire was used to gather primary data, and statistical analysis (including factor analysis and the chi-square test) was conducted on the questionnaire results. The results of the empirical research showed that respondents could be divided into three groups. One group exclusively included people who showed willingness for active participation in the creation of a marketing offer for native products. This was the most homogenous group. The other two groups contained respondents who did not show willingness for prosumption. The article is original because it uses quite a new approach of analysing the importance of ethnocentric attitudes for purchasers’ willingness for prosumption. Prior to this article, prosumption and ethnocentrism had not been analysed together.