Hypromellose (INN), short for hydroxypropyl methylcellulose (HPMC), is a semisynthetic, inert, viscoelastic polymer used as eye drops, as well as an excipient and controlled-delivery component in oral medicaments, found in a variety of commercial products.

As a food additive, hypromellose is an emulsifier, thickening and suspending agent, and an alternative to animal gelatin.

Its Codex Alimentarius code (E number) is E464.