The study aimed to explore the relationship between eosinophils and the prognosis of varicella in adults. We retrospectively reviewed the medical records of patients who were hospitalized in The Fifth People's Hospital of Suzhou with a diagnosis of adult varicella during the period between 1 January 2012 and 31 December 2020. Of the 359 patients, 228 (63.51%) had eosinopenia. The proportion of patients with mild type disease was significantly lower in the eosinopenia group than in the noneosinopenia group (50.44% vs. 65.65%, P=0.006). The proportion of the patients with common type disease was significantly higher in the eosinopenia group than in the noneosinopenia group (39.47% vs. 28.24%, P=0.039).The proportion of the patients with severe type disease was higher in the eosinopenia group, although the difference did not reach statistical significance (10.09% vs. 6.11%, P = 0.243).