With breakthrough advances and accelerated industrial expansion in brain-computer interface (BCI) technology, its ethical implications have increasingly garnered academic attention. Based on scientometrics and combined with interdisciplinary and risk-evolution analytical perspectives, this study examines the landscape, knowledge base, and research hotspots in international research on the ethics of brain-computer interface: (1) Publications in research on the ethics of brain-computer interface demonstrate a three-stage evolutionary trajectory, with fluctuations closely linked to technological cycles, social events, and policy shifts, culminating in 2024 as a window of explosive growth. (2) Bioethics, cognitive neuroscience, and machine ethics form a modular interdisciplinary citation network spanning normative values, technical pathways, and human-machine collaboration frameworks, thereby supporting a multidimensional theoretical foundation. (3) Research hotspots have formed clusters in the domains of subjectivity, technology, and society, highlighting the dynamic characteristics of risk evolution. (4) With the deepening of brain-computer integration, issues concerning the neural rights of integrated subjects and social acceptance urgently require attention. Based on the assessment of the current situation, future research should focus on fostering interdisciplinary empirical collaboration, driving industrial optimization and upgrading, and promoting decentralized network governance, so as to contribute to the improvement and development of global research on the ethics of brain-computer interface.