Background: Medical personnel, especially nurses, are at the forefront of the global COVID-19 epidemic. This study was conducted with the aim to evaluate the level of health anxiety in nurses caring for patients with COVID-19. Materials and Methods: This cross-sectional, descriptive study was performed on the 340 nurses working in 3 selected educational and medical centers affiliated with Zanjan University of Medical Sciences, Iran. The participants were selected through census method in April and May 2020. The instrument used was the Health Anxiety Inventory. It includes 18 items in 3 subdomains. Descriptive statistics and the nonparametric Mann–Whitney U and Kruskal–Wallis tests were used to analyze the data. Results: The mean (SD) total health anxiety score of nurses was 24.68 (4.30), and 91.76% of participants had moderate health anxiety. Moreover, there was a statistically significant relationship between health anxiety level and the demographic variables of gender (Z = −4.54, p < 0.001), marital status (χ 2 3 = 32.54, p < 0.001), parenting (Z = −4.16, p < 0.001), family relationships (Z = −2.30, p = 0.020), work experience (χ 2 4 = 19.32, p < 0.001), and the workplace (χ 2 2 = 41.24, p < 0.001) Conclusions: The results showed that the level of health anxiety of nurses who cared for COVID-19 patients was moderate. Therefore, it is recommended that the necessary measures be taken to manage health anxiety in this group.