Mitochondrial DNA (mtDNA) copy number correlates with tumor pathology in some cancers.To investigate mtDNA copy number in head and neck cancer (HNC).mtDNA copy number was determined and compared between HNC patients and malignancy-free controls.The mtDNA copy number was significantly higher in HNC patients, increased with cancer progression and correlated negatively with patient survival.mtDNA copy number appears to be associated with HNC stage and survival, but confirmation requires similar studies in larger cohorts.Studies to establish the nature of the relationship between mtDNA copy number and HNC are warranted.