Cluster headache (CH) consists of attacks of severe, unilateral orbital/supraorbital/temporal pain, lasting for 15–180 min, occurring once or more times a day, and associated with ipsilateral conjunctival injection, lacrimation and other symptoms. Cataract is clouding of the lens of the eye causing a progressive and painless loss of vision. We describe the cases of two men (not relative, but with the same last name, which originates from north-eastern Italy) that in young adult age, after years of suffering from chronic CH, developed cataract on the same side of the pain attacks. Patient 1 was diagnosed as having cataract 18 years after the onset of episodic (and subsequently chronic) CH. Patient 2 began suffering from chronic CH at the age of 44 years and after 8 years he developed cataract. This is the first report of cataract in patient suffering of CH and occurring in the eye affected by the pain attack.