This article begins with the question of whether translation should be regarded as a human-centered or a posthuman endeavor, examining how the deep involvement of technology in translation practice has reshaped translational subjectivity. It first traces the philosophical origins of the human-centered and posthuman paradigms and, drawing on insights from theories of subjectivity and intersubjectivity, the philosophy of technology, and the sociology of technology, explicates their implications for translation. From this perspective, it delineates the evolution of translational subjectivity: from the text-centered stage in the mid-to-late twentieth century, where the seeds of a human-centered paradigm began to emerge, to the translator-centered stage around the turn of the twenty-first century, where the human-centered orientation reached full expression, and further toward the human-machine collaborative mode in the era of generative AI, which signals a posthuman turn. Building on this trajectory, the article proposes an analytical framework of collaborative subjectivity, highlighting the stratified, dynamic, and fluid mechanisms through which human translators and AI systems co-construct subjectivity in the translation process. The framework aims to avoid the over-humanization inherent in the human-centered paradigm while also transcending the radical de-centering of the human in the posthuman turn, thereby revealing the complex transformation of translational subjectivity under technological waves. Theoretically, this study seeks to correct the binary narrative of human-machine opposition and to broaden the explanatory dimensions of research on translational subjectivity. Practically, it offers strategic insights for translation education, industry governance, and technological development.