To perform a mental health evaluation and an early psychological intervention for healthcare workers (HCWs) during the coronavirus disease 2019 (COVID-19) epidemic, an online survey was conducted among 3055 HCWs in the paediatric intensive care units (PICUs) of 62 hospitals in China on March 26, 2020, by the Neurology and Sedation Professional Group, Emergency Department, Paediatrics Branch, Chinese Medical Association. The questionnaire was divided into three parts, including general information, the Impact of Event Scale-Revised (IES-R), and the Depression Anxiety Stress Scale-21 (DASS-21). The results show that a total of 970 HCWs (45.99%) were considered to meet the clinical cut-off scores for posttraumatic stress (PTS), and the proportions of participants with mild to extremely severe symptoms of depression, anxiety and stress were 39.69%, 36.46% and 17.12%, respectively. There was no significant difference in the psychological impact among HCWs of different genders. Married HCWs were 1.48 times more likely to have PTS than unmarried HCWs (95% Cl: 1.20-1.82, p <0.001). Compared with junior professional title participants, the PTS-positive rate of HCWs with intermediate professional titles was 1.91 times higher (90% Cl: 1.35-2.70, p<0.01). Those who had been in contact with confirmed COVID-19 cases were 1.40 times (95% Cl: 1.02-1.92, p <0.05) more likely to have PTS than those who did not have contact with COVID-19 cases or did not know the relevant conditions. For depression, the proportion of HCWs with intermediate professional titles was significantly higher, at 1.65 times (90% Cl: 1.17-2.33, p <0.01) that of those with junior professional titles. The depression of HCWs at work during the epidemic was 1.56 times that of HCWs on vacation (95% Cl: 1.03-2.37, p <0.05), and their anxiety was 1.70 times greater (95% Cl: 1.10-2.63, p <0.05). Participants who had been in contact with confirmed COVID-19 cases had more pronounced anxiety, 1.40 times that of those who did not have contact with COVID-19 cases or did not know the relevant conditions (95% Cl: 1.02-1.92, p <0.05). There was no significant correlation between the variables and the positive results of stress symptoms. In total, 45.99%, 39.69%, 36.46% and 17.12% of PICU HCWs were affected by PTS, depression, anxiety and stress, respectively, to varying degree. Married status, intermediate professional titles and exposure history were independent risk factors for PTS. Intermediate professional titles and going to work during the epidemic were independent risk factors for depression, and going to work and exposure history during the epidemic were independent risk factors for anxiety. In the face of public health emergencies, HCWs not only specialize in paediatric intensive care but also, as a high-risk group, must actively take preventive measures and use mitigation strategies.