胆囊收缩素（英语：cholecystokinin，简称CCK或CCK-PZ；词源来自于希腊语的chole，胆汁之意；cysto，囊状之意；kinin，移动之意；组合起来的意义为「移动胆汁之囊」）是一种消化系统当中的肽类激素，可以促进脂肪与蛋白质的消化。胆囊收缩素在此之前名为促胰酶素（pancreozymin），是由小肠的黏膜上皮细胞当中的I细胞所合成，并由十二指肠分泌；这会导致从胰脏与胆囊，各自释放消化酶与胆汁。胆囊收缩素也是一种食欲抑制剂。最近的证据暗示，胆囊收缩素在促进鸦片类药物的药物容许量，如吗啡和海洛因，扮演着重要角色，并且在经历鸦片类药物停药后的疼痛过敏经历有着部份的关联性。

Cholecystokinin (CCK or CCK-PZ; from Greek chole, "bile"; cysto, "sac"; kinin, "move"; hence, move the bile-sac (gallbladder)) is a peptide hormone of the gastrointestinal system responsible for stimulating the digestion of fat and protein. Cholecystokinin, previously called pancreozymin, is synthesized and secreted by enteroendocrine cells in the duodenum, the first segment of the small intestine, and causes the release of digestive enzymes and bile from the pancreas and gallbladder, respectively. It also acts as a hunger suppressant. Recent evidence has suggested that it also plays a major role in inducing drug tolerance to opioids like morphine and heroin, and is partly implicated in experiences of pain hypersensitivity during opioid withdrawal.