BACKGROUND: Studying global health problems requires international multidisciplinary teams. Such multidisciplinarity and multiculturalism create challenges in adhering to a set of ethical principles across different country contexts. Our group on health system responses to violence against women (VAW) included two universities in a European high-income country (HIC) and four universities in low-and middle-income countries (LMICs). This study aimed to investigate professional and policy perspectives on the types, causes of, and solutions to ethical challenges specific to the ethics approval stage of the global research projects on health system responses to VAW. METHODS: We used the Network of Ethical Relationships model, framework method, and READ approach to analyse qualitative semi-structured interviews (n = 18) and policy documents (n = 27). In March-July 2021, we recruited a purposive sample of researchers and members of Research Ethics Committees (RECs) from the five partner countries. Interviewees signposted policies and guidelines on research ethics, including VAW. RESULTS: We developed three themes with eight subthemes summarising ethical challenges across three contextual factors. The global nature of the group contributed towards power and resource imbalance between HIC and LMICs and differing RECs' rules. Location of the primary studies within health services highlighted differing rules between university RECs and health authorities. There were diverse conceptualisations of VAW and vulnerability of research participants between countries and limited methodological and topic expertise in some LMIC RECs. These factors threatened the timely delivery of studies and had a negative impact on researchers and their relationships with RECs and HIC funders. Most researchers felt frustrated and demotivated by the bureaucratised, uncoordinated, and lengthy approval process. Participants suggested redistributing power and resources between HICs and LMICs, involving LMIC representatives in developing funding agendas, better coordination between RECs and health authorities and capacity strengthening on ethics in VAW research. CONCLUSIONS: The process of ethics approval for global research on health system responses to VAW should be more coordinated across partners, with equal power distribution between HICs and LMICs, researchers and RECs. While some of these objectives can be achieved through education for RECs and researchers, the power imbalance and differing rules should be addressed at the institutional, national, and international levels. Three of the authors were also research participants, which had potential to introduce bias into the findings. However, rigorous reflexivity practices mitigated against this. This insider perspective was also a strength, as it allowed us to access and contribute to more nuanced understandings to enhance the credibility of the findings. It also helped to mitigate against unequal power dynamics.