1,2-Naphthoquinone or ortho-naphthoquinone is a polycyclic aromatic organic compound with formula C10H6O2.

This yellow solid is prepared by oxidation of 1-amino-2-hydroxynaphthalene with ferric chloride.

[1] This diketone (an ortho-quinone) is a metabolite of naphthalene.

[2] It is also found in diesel exhaust particles.

The accumulation of this toxic metabolite in rats from doses of naphthalene has been shown to cause eye damage, including the formation of cataracts.