ABSTRACT Across three vignette-based experiments (N = 697) primarily involving young adults from China, our research systematically examines the moral judgments and perceived identity changes associated with technological implants, unveiling “naturalness bias” as a pivotal psychological mechanism influencing these judgments. Study 1 scrutinized the effects of physical enhancements via body implants, revealing a significant link between perceived low naturalness, negative moral judgment, and a reduced intention to adopt such technologies. Moreover, individuals who receive technological implants were perceived as more inclined toward immoral behavior, resulting in a considerable shift in identity perception. Study 2 confirmed these findings and introduced a control group of plastic surgery vignette to refine comparisons and enhance methodological rigor. Study 3 broadened the scope to include both emotional and cognitive enhancements via implants. It found that emotional enhancements were judged more critically regarding morality and naturalness, leading to greater perceived identity changes and higher expectations of immoral behavior compared to cognitive enhancements. Collectively, the current research provides essential insights into the ethical dimensions of transhumanist technologies, highlighting the profound moral considerations and identity implications of adopting such enhancements.