Introduction: To reduce inappropriate polypharmacy, deprescribing should be part of patients' regular care. Yet deprescribing is difficult to implement, as shown in several studies. Understanding patients' attitudes towards deprescribing at the individual and country level may reveal effective ways to involve older adults in decisions about medications and help to implement deprescribing in primary care settings. In this study we aim to investigate older adults' perceptions and views on deprescribing in different European countries. Specific objectives are to investigate the patients' willingness to have medications deprescribed by medication type and to have herbal or dietary supplements reduced or stopped, the role of the Patient Typology (on medication perspectives), and the impact of the patient-GP relationship in these decisions. Methods and analysis: This cross-sectional survey study has two parts: Part A and Part B. Data collection for Part A will take place in nine countries, in which per country 10 GPs will recruit 10 older patients (>= 65 years old) each (n = 900). Part B will be conducted in Switzerland only, in which an additional 35 GPs will recruit five patients each and respond to a questionnaire themselves, with questions about the patients' medications, their willingness to deprescribe those, and their patient-provider relationship. For both Part A and part B, a questionnaire will be used to assess the willingness of older patients with polypharmacy to have medications deprescribed and other relevant information. For Part B, this same questionnaire will have additional questions on the use of herbal and dietary supplements. Discussion: The international study design will allow comparisons of patient perspectives on deprescribing from different countries. We will collect information about willingness to have medications deprescribed by medication type and regarding herbal and dietary supplements, which adds important information to the literature on patients' preferences. In addition, GPs in Switzerland will also be surveyed, allowing us to compare GPs' and patients' views and preferences on stopping or reducing specific medications. Our findings will help to understand patients' attitudes towards deprescribing, contributing to improvements in the design and implementation of deprescribing interventions that are better tailored to patients' preferences.