Background: COVID-19 crisis has changed the conditions of many throughout the globe. One negative consequence of the on-going pandemic is anxiety brought by uncertainty and the COVID-19 disease. Increased anxiety is a potential risk factor for wellbeing at work. This study investigated psychological, situational, and socio-demographic predictors of COVID-19 anxiety using longitudinal data. Methods: Nationally representative sample of Finnish workers (N = 1308) was collected before and during the COVID-19 crisis. Eighty percent of the participants responded to the follow-up study (N=1044). COVID-19 anxiety was measured with a modified Spielberger State–Trait Anxiety Inventory. Psychological and situational predictors included perceived loneliness, psychological distress, technostress, personality, social support received from work community, and remote working. Also, number of socio-demographic factors were investigated. Results: Perceived loneliness, psychological distress, technostress, and neuroticism were identified as robust psychological predictors of COVID-19 anxiety. Increase in psychological distress and technostress during the COVID-19 crisis predicted higher COVID-19 anxiety. Recent change in work field and decreased social support from work community predicted COVID-19 anxiety. Women and young people experienced higher anxiety. Conclusions: Different factors explain workers’ COVID-19 anxiety. Increased anxiety can disrupt wellbeing at work, emphasizing organizations’ role in maintaining an inclusive and caring work culture and providing technical and psychological support to workers during crisis.