Polymer electrolyte membrane fuel cells (PEMFCs) feature high energy densities, low operating temperatures, and low environmental impact, which make them a promising technology for power applications. As a key component of PEMFCs, Pt-based catalysts are still under widespread investigation and have shown exciting performance; however, to move towards their successful commercialization, focusing solely on their catalytic activity is not sufficient. Instead, more effort is required to improve their stability and to decrease costs. Herein, we provide a comprehensive review of current research activities that have concentrated on how to stabilize the Pt-based catalysts. We devote the most attention to the structure-optimization of the Pt-based catalysts and the development of advanced supports. The feasible strategies for structure optimization are subdivided into three groups: 1) dimension effects; 2) electronic and bifunctional effects; and 3) steric effects. Then, we discuss the techniques that have been developed for improving carbon black and for generating various types of carbon-free supports and composites supports (e.g., graphite, carbon nanotubes, new-type oxides and nitrides, and macromolecules). An outlook on the future trends and developments in this area is also provided at the end of the review.