BackgroundHeadache is the most common COVID-19-related neurological symptom. But, diagnostic clues of headache for COVID-19 infection are not well known. MethodsWe developed a detailed web-based questionnaire screening the characteristics and course of headaches besides clinical COVID-19 features. The participants were grouped according to being diagnosed with COVID-19 infection or not, and having previous or new-onset headaches. The COVID-19 related headache features and their associations with other clinical features were investigated. A binary logistic regression model was performed to differentiate the characteristics of headache related to COVID-19. Findings 3458 participants (2341 females;67.7%, 1495 healthcare workers;43.2%) with a mean age of 43.21±11.2 years experiencing headache during pandemic contributed to the survey. Among them, 262 participants had COVID-19 and 126(48.1%) were male. The rate of males in the group without COVID-19 was 31% (991 out of 3196 participants) showing significant gender difference between groups (p<0.000). COVID-19 related headaches were more closely associated with anosmia/ageusia and gastrointestinal complaints (RR=3.7 and RR=1.33, respectively), showed different characteristics like pulsating, pressing, and even stabbing quality. Logistic regression analyses showed that bilateral headache, duration over 72 hours, analgesic resistance and having male gender were significant variables to differentiate COVID-19 positive patients from those without COVID-19 (p<0.000 for all variables). A worsening of previous primary headaches due to the pandemic-related problems was not the rule in majority of patients.Interpretation Bilateral, long-lasting headaches, resistance to analgesics and having male gender were more frequent in people with COVID-19 in conjunction with the anosmia/ageusia and gastrointestinal complaints. These features may be helpful for COVID-19 diagnosis in the clinical evaluation of headache patients during the pandemic.Funding: This study was funded by Scientific Research Projects Coordination Unit of Istanbul University with a project number of GAP-36802.