© 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.The aim of the study was to explore the relationships among cyberchondria, fear of COVID-19, health anxiety, obsessions, sleep quality, and negative affect in a national community sample of Turkish participants. A sample of 8,276 volunteers, aged between 18 and 65, were recruited via an online platform. The Perceived Vulnerability about Diseases Questionnaire, Fear of COVID-19 Scale, Cyberchondria Severity Scale, Short Health Anxiety Inventory, Depression Stress Anxiety Scale-21, Obsessive–Compulsive Inventory–Revised, and Pittsburgh Sleep Quality Index were completed by participants. Data were analyzed using mixture structural equation modelling approach. Results revealed that perceived vulnerability to disease was found to be positively related with cyberchondria, poor sleep quality, health anxiety, and obsessive–compulsive symptoms. Negative affect was positively associated with obsessive–compulsive symptoms, fears of COVID-19, cyberchondria severity, and poor sleep quality. Additionally, fear of COVID-19 was positively related to health anxiety. Also, cyberchondria severity was found to be positively associated with poor sleep quality and obsessive–compulsive symptoms. Mixture analysis classified participants into six latent classes: 1) Risk-Aversive Healthy Group, 2) Incautious Healthy Group, 3) Infection Obsessions Group, 4) Health Anxiety Group, 5) Negative Affect Group, and 6) General Psychopathology Group. The national survey data showed that perceived vulnerability to diseases, negative affect, fear of COVID-19, cyberchondria, health anxiety, obsessive–compulsive symptoms, and sleep quality appeared to be at the center of pandemic health anxiety.