Objectives: The SARS-CoV-2 pandemic has affected the development of negative phenomena such as anxiety symptoms, a tendency to use alcohol and aggressive behaviors. It is postulated to investigate the factors limiting the development of the indicated adverse effects. One of the psychological resources that may have a significant, pro-health character in relation to mental functioning is ego-resiliency (ER). It is described as a personality trait associated with a high ability to adequately regulate self-control, depending on the conditions. There are studies providing information about the prohealth, adaptive nature of ER during the COVID‑19 period. The aim of the study was to assess the relationships between ER and anxiety, the tendency to use alcohol and aggression in the group of Polish people in the initial lockdown period in Poland. Material and Methods: Overall, 538 adult Polish people participated in the study. The Ego-Resiliency Scale referred to as ER89-R12, according to Block’s concept, was used to measure ER. The other scales used were the General Anxiety Disorder Scale, the Alcohol Use Disorder Identification Test, and the Buss-Perry Aggression Questionnaire. Statistical analyses were performed using Spearman’s rank correlation coefficient, the multiple regression procedure, the Mann-Whitney U test and the Kruskal-Wallis rank ANOVA. Cronbach’s α coefficients were also assessed. Results: Statistically significant negative relationships between ER and the severity of anxiety symptoms and generalized aggression were found. There was a weak positive relationship between ER and the tendency to use alcohol. Among the surveyed Polish people, higher ER was characteristic of the older respondents (aged >29 years) and people with higher education. Conclusions: Ego-resiliency in the times of the SARS-CoV-2 pandemic can counteract the development of anxiety and aggression. Optimal regulation seems to play an important role in this relationship. The relationship between resiliency and the tendency to use alcohol requires further observation. Int J Occup Med Environ Health. 2021;34(2):289–300