恒星物理学，是天体物理学的一个分支，是研究恒星的一生以及致密天体（如白矮星、中子星）的学科。

Stellar physics, is a term coined for the research concerning the formation, evolution, interior and the atmospheres of stars. The understanding of the birth and death of stars requires the application of almost all branches of modern physics. These areas include; gravitation, hydrodynamics, atomic physics, liquid-solid state theory, superconductivity and superfluidity. This distinguishes it from stellar dynamics, which concerns mainly gravitational interactions between stars.