Background. The COVID-19 pandemic has been an unprecedented social and health emergency worldwide. Cross-cultural research on mental health during this situation is needed to better understand its consequences. Objective. To evaluate the different psychological impacts of the crisis and lockdown situation during the first six weeks of COVID emergency measures in samples of the Spanish and Russian populations. Design. A cross-sectional study was conducted through an online survey (NSpain = 1041; NRussia = 743). The prevalence of loneliness, depression, anxiety, perceived discrimination (PD), internalized stigma (IS), and perceived social support (PSS) was evaluated. Chi-square tests and t-tests were administered. The Enter Method were used to identify the predictors of the mental health impact. Results. Differences were found between the Russian and the Spanish populations. While the degrees of anxiety and depression did not differ significantly, loneliness, the alienation dimension of IS, and PD were more pronounced in the Russian respondents. In Spain, the predictor of less negative impact was PSS from various sources, while in Russia we only found PSS from the family. Conclusion. Although in both countries the impact at the clinical level seemed to be similar, differences were found at the psychosocial level. Variables with a strong cultural component may be key to determining the means of alleviating the effects of the crisis, with PSS being a fundamental protective factor. More crosssectional studies are needed to understand the impact of the pandemic in depth. © 2020. Lomonosov Moscow State University. All Rights Reserved.