生理学（英语：physiology英语发音：/ˌfɪziˈɒlədʒi/; 来自古希腊语φύσις (physis)，意即：“nature, origin”,和-λογία (-logia)，意即：“study of” ） 是生物学的一门子领域，研究生物体及其各组成部分，在活体系统中化学或物理的功能活动。

生理学一般被分为植物生理学和动物生理学，但生理学的基本原理是对地球上所有的生物来说一致的。比如许多研究酵母的细胞的生理学结果也可以运用在人的细胞中。

动物生理学包括人类生理学和其他动物的生理学，植物生理学也从这个分支的许多成果获益。

Physiology (/ˌfɪziˈɒlədʒi/; fromAncient Greekφύσις (physis), meaning "nature, origin",and-λογία (-logia), meaning "study of") is the scientific study of the normal function in living systems. A sub-discipline of biology, its focus is in how organisms, organ systems, organs, cells, and biomolecules carry out the chemical or physical functions that exist in a living system. Given the size of the field, it is divided into, among others, animal physiology (including that of humans), plant physiology, cellular physiology, microbial physiology (see microbial metabolism), bacterial physiology, and viral physiology. The Nobel Prize in Physiology or Medicine is awarded to those who make significant achievements in this discipline by the Royal Swedish Academy of Sciences. In medicine, a physiologic state is one occurring from normal body function, rather than pathologically, which is centered on the abnormalities that occur in animal diseases, including humans.