The term "petroselinic" means related to, or derived from, oil of Petroselinum, parsley.

[3] Petroselinic acid occurs in high amounts in plants in Apiaceae, Araliaceae,[4] Griselinia (Griseliniaceae)[5] and in Garryaceae.

[7] In addition, petroselinic acid has been found in minor amounts in several fats of plant and animal origin, including in human sources.

Fatty acids mostly occur as their esters, commonly the triglycerides, which are the greasy materials in many natural oils.

In chemical analysis, petroselinic acid can be separated from other fatty acids by gas chromatography of methyl esters; additionally, a separation of unsaturated isomers is possible by argentation thin-layer chromatography.