苯基是从苯（C₆H₆）获得的一个疏水性芳香族官能团。它的分子式为-C₆H₅。它经常简写为-Ph。这种烃基可在许多有机化合物中找到，苯酚、苯胺等分子结构中都含有这种基团。

In organic chemistry, the phenyl group or phenyl ring is a cyclic group of atoms with the formula C₆H₅. Phenyl groups are closely related to benzene and can be viewed as a benzene ring, minus a hydrogen, serving as a functional group. Phenyl groups have six carbon atoms bonded together in a hexagonal planar ring, five of which are bonded to individual hydrogen atoms, with the remaining carbon bonded to a substituent. Phenyl groups are commonplace in organic chemistry. Although often depicted with alternating double and single bonds, phenyl groups are chemically aromatic and show nearly equal bond lengths between carbon atoms in the ring.