Mental resilience is the ability to bounce back from daily life stressors such as divorce or losing a job. Extensive research has demonstrated a negative relationship between mental resilience and alcohol consumption. That is, both the quantity and frequency of alcohol consumption are greater in individuals with lower levels of mental resilience. There has, however, been little scientific attention paid to the relationship between mental resilience and alcohol hangover severity. The objective of this study was to evaluate psychological factors that may impact the frequency and severity of alcohol hangovers, including alcohol intake itself, mental resilience, personality, baseline mood, lifestyle, and coping mechanisms. An online survey was conducted among Dutch adults (N = 153) who had a hangover after their heaviest drinking occasion in the period before the start of the COVID-19 pandemic (15 January to 14 March 2020). Questions were asked about their alcohol consumption and hangover severity on their heaviest drinking occasion. Mental resilience was assessed with the Brief Mental Resilience scale, personality with the Eysenck Personality Questionnaire–Revised Short Scale (EPQ-RSS), mood via single item assessments, and lifestyle and coping with the modified Fantastic Lifestyle Checklist. The partial correlation, corrected for estimated peak blood alcohol concentration (BAC), between mental resilience and hangover severity was not significant (r = 0.010,p= 0.848). Furthermore, no significant correlations were found between hangover severity or frequency and personality and baseline mood. For lifestyle and coping factors, a negative correlation was found between the use of tobacco and toxins (i.e., drugs, medicines, caffeine) and the frequency of experiencing hangovers. Regression analysis revealed that hangover severity after the heaviest drinking occasion (31.2%) was the best predictor of hangover frequency, and that subjective intoxication on the heaviest drinking occasion (38.4%) was the best predictor of next-day hangover severity. Mood, mental resilience, and personality were not relevant predictors of hangover frequency and severity. In conclusion, mental resilience, personality, and baseline mood do not predict hangover frequency and severity.