It is well recognized that, in general, chronic inflammation can predispose to malignant change. There is however, to our knowledge, no previously reported association between chronic obstructive sialadenitis and salivary gland epithelial malignancy. We describe here the first reported example in the English literature of a salivary duct carcinoma arising in a parotid gland with a long history of chronic obstructive sialadenitis. It is possible that a causal relationship exists between the two conditions. If this were the case then non-surgically treated chronic obstructive sialadenitis patients may well warrent careful clinical follow-up.