Abstract T cells, as one of the most abundant immune cell types in the human body, play a central role in therapeutic applications and currently dominate the clinical landscape of cell therapies. Their target specificity and capacity to generate durable therapeutic responses make them a powerful modality for precision therapy. T cell therapies represent a leading frontier in cellular medicine and have been investigated for a broad spectrum of indications, from cancers to autoimmune diseases. Here, we provide a detailed overview of the clinical landscape of T cell therapies. We outline the historical developments that shaped the evolution of T cells into transformative therapies and present a comprehensive analysis of their clinical translation. We discuss key milestones in T cell discovery and provide an overview of the 19 globally approved T cell therapy products. We then examine the core features of these approved products and conduct an in‐depth analysis of 2570 clinical trials involving T cell therapies, identifying three distinct time intervals of growth in clinical activity. Furthermore, we evaluate the evolution of critical trial parameters, such as cell source, disease indication, target selection, and delivery route, highlighting emerging trends and key inflection points. Lastly, we discuss the biological and logistical challenges that limit the broader clinical translation of T cell therapies to new indications and diverse patient populations. Our findings indicate a steady rise in clinical studies and regulatory approvals for T cell therapies, with a notably higher rate of approved products in recent years compared to stem cell therapies. This growth exhibits a phased pattern, with each interval characterized by a major inflection point in scientific advancement and clinical translation. Our discussions will provide a quantitative and contextualized overview of this clinical progress in T cell therapy, offering insights into its current trajectory and future potential as a transformative class of therapeutics.