二磷酸鸟苷（Guanosine diphosphate，缩写GDP），也称鸟苷二磷酸，是一种核苷酸，组成物是焦磷酸基团、五碳糖、以及碱基鸟嘌呤。

GDP是三磷酸鸟苷（GTP）经过去磷酸化之后的产物，催化此作用的酵素是GTP酶。

Guanosine diphosphate, abbreviated GDP, is a nucleoside diphosphate. It is an ester of pyrophosphoric acid with the nucleoside guanosine. GDP consists of the pyrophosphate group, the pentose sugar ribose, and the nucleobase guanine.

GDP is the product of GTP dephosphorylation by GTPases, e.g., the G-proteins that are involved in signal transduction.