三磷酸胞苷（英语：cytidine triphosphate, CTP）是一种核苷酸，为合成RNA的原料之一。CTP与ATP同为高能分子，但与ATP相较之下较少作为能量来源。CTP可参与甘油磷脂的合成或蛋白质的糖基化。

Cytidine triphosphate is a pyrimidine nucleoside triphosphate.

CTP is a substrate in the synthesis of RNA.

CTP is a high-energy molecule similar to ATP, but its role as an energy coupler is limited to a much smaller subset of metabolic reactions. CTP is a coenzyme in metabolic reactions like the synthesis of glycerophospholipids and glycosylation of proteins.