Introduction: The increasing availability of biosimilars can increase patient access to these drugs and reduce the economic burden. Nurses play a key role in the education, administration, pharmacovigilance and management of the side effects of biosimilars. The aim of this study was to assess the knowledge and attitudes of nurses towards biosimilar drugs in different countries. Methods: An international cross-sectional study was conducted from November 2021 to February 2022. The survey was carried out using Computer-Assisted Web Interview (CAWI), sent by the CAWI panel via the website. Results: The results showed that nurses with a greater level of education felt most knowledgeable about biosimilars (chi(2) = 105.813, df = 2, p < 0.001). One-third of nurses with a doctorate and a second degree said biosimilars are used in their workplace (chi(2) = 48.169, df = 4, p < 0.001); most nurses with a second degree said that they had never heard of biosimilars (41%). Doctorate-level nurses thought knowledge is the key factor to increasing biosimilar uptake (97%). Conclusions: Nurses are not knowledgeable about biosimilars. Most would like to participate in training on biosimilars. This is a very important topic, because biosimilars are constantly evolving in medicine.