The zonule of Zinn is a ring of fibrous strands connecting the ciliary body with the crystalline lens of the eye. The zonules hold the lens in place and function to change the focusing power of the eye by changing the tension of the zonules by contraction and relaxation of the ciliary muscle.

The zonule of Zinn is also known as Zinn's membrane and the zonula ciliaris. Named for Johann Gottfried Zinn.

Eye | Eponymous anatomical structures