Cause-related marketing (CRM) is a strategic tool that can link selling products with supporting a social cause. However, not all CRM campaigns are effective in terms of influencing consumer decisions. In our research, we explore the role of beneficiary origin in reactions to CRM campaigns created by brands either of national or foreign origin. We explore also the role of consumer ethnocentrism, defined as a preference for national brands and products, as a factor influencing the relations between beneficiary and brand origin. The online experiment was conducted on a sample of 549 participants. Six versions of a CRM advertisement were created (2 brands x 3 types of beneficiary). Participants were asked to evaluate the advertisement, estimate their product and firm perception, as well as their purchase intention. Consumer ethnocentrism was also measured. Results generally showed that the beneficiary type influenced advertisement evaluation, whereas brand origin influenced product and firm perception as well as purchase intention. Similar results were observed among subjects with a low consumer ethnocentrism. However, in the case of subjects with a high consumer ethnocentrism, only product perception changed under the influence of the experimental conditions and a significant interaction effect was observed. The product of a national brand was perceived better when the company helped in-group beneficiaries rather than out-group ones. However, when the product was of national brand, it was perceived as better in the case of helping an out-group than an in-group beneficiary.