Isoamyl acetate, also known as isopentyl acetate, is an organic compound that is the ester formed from isoamyl alcohol and acetic acid. It is a colorless liquid that is only slightly soluble in water, but very soluble in most organic solvents. Isoamyl acetate has a strong odor (similar to Juicy Fruit, a foam banana sweet or a pear drop) which is also described as similar to both banana and pear. Banana oil is a term that is applied either to pure isoamyl acetate or to flavorings that are mixtures of isoamyl acetate, amyl acetate, and other flavors.

Isoamyl acetate is used to confer banana flavor in foods. Pear oil commonly refers to a solution of isoamyl acetate in ethanol that is used as an artificial flavor.

It is also used as a solvent for some varnishes and nitrocellulose lacquers, as well as being a honey bee pheromone and can be used to attract large groups of honeybees to a small area.

As a solvent and carrier for materials such as nitrocellulose, it was extensively used in the aircraft industry for stiffening and wind-proofing fabric flying surfaces, where it and its derivatives were generally known as 'dope.' Now that most aircraft are all-metal, such use is now limited to model aircraft, where it is still popularly used for strengthening tissue coverings and balsa wood.

Because of its intense, pleasant odor and its low toxicity, isoamyl acetate is used to test the effectiveness of respirators or gas masks. Isoamyl acetate is released by a honey bee's sting apparatus where it serves as a pheromone beacon to attract other bees and provoke them to sting.