As a cutting-edge personalized treatment method, CAR-T cell technology transforms patients' own T cells through genetic engineering, making them have the ability to specifically identify and kill tumor cells. The aim of this paper is to thoroughly organize the foundational principles and clinical utility of CAR-T cell technology, highlighting its recent advancements in treating both hematological and solid tumors. Through a comprehensive assessment of CAR-T cell technology's efficacy and risks, this study aims to inform clinical decision-making. Initially, the paper outlines the basic mechanisms of CAR-T cell technology, followed by an analysis of its notable therapeutic outcomes in hematological tumors. Additionally, it addresses the challenges posed by solid tumor treatment, including antigen expression complexity and tumor microenvironment impact. Emphasis is placed on the crucial role of regulatory bodies in enhancing oversight and developing risk management strategies to safeguard patient safety.