Triethyl borate is a colorless liquid with the formula B(OCH2CH3)3.

[1] It is a weak Lewis acid (AN = 17 as measured by the Gutmann–Beckett method).

[2] It burns with a green flame and solutions of it in ethanol are therefore used in special effects and pyrotechnics.

It is used as a solvent and/or catalyst in preparation of synthetic waxes, resins, paints, and varnishes.

It is used as a component of some flame retardants in textile industry and of some welding fluxes.