Uridine monophosphate (UMP), also known as 5′-uridylic acid (conjugate base uridylate), is a nucleotide that is used as a monomer in RNA.

UMP consists of the phosphate group, the pentose sugar ribose, and the nucleobase uracil; hence, it is a ribonucleotide monophosphate.

Uncatalyzed, the decarboxylation reaction is extremely slow (estimated to occur on average one time per 78 million years).

In a study, gerbils fed a combination of uridine monophosphate, choline, and docosahexaenoic acid (DHA) were found to have significantly improved performance in running mazes over those not fed the supplements, implying an increase in cognitive function.

Non-phosphorylated uridine is not bioavailable beyond first-pass metabolism, as it is almost entirely catabolised in the liver and gastrointestinal tract.