Insomnia disorder is the second most prevalent mental disorder, and it is a primary risk factor for depression (Blanken et al., 2019), cancer (Akman et al.,2015) and many others health issues. Personality traits are known to be associated with overall sleep quality and also with overall arousal (Cellini et al. 2017). The aim of this study was to explore links between personality traits, hyperarousal and severity of insomnia during Covid-19 pandemic. MINI-IPIP and the Perfectionism Inventory were used to measure personality traits, PSAS to measure pre-sleep arousal and ISI to measure severity of insomnia. Our sample consisted of 567 respondents. We found significant correlation between perceived insomnia severity and Neuroticism (r=0,321, p<0,001), Extraversion (r=-0,180, p<0,001) and Perfectionism (r=0,274, r<0.001). Link between the same personality traits and degree of pre-sleep arousal was confirmed as well: Neuroticism (r=0,424, p<0,001), Extraversion (r=-0,247, p<0,001), Perfectionism (r=0,295, r<0,001). Further analysis revealed positive correlation between Rumination subscale of Perfectionism Inventory and Cognitive subscale of Pre-sleep arousal scale (r=521, p<0,001). In addition, more that 60 % of our sample reported at least some symptoms of insomnia, which is more than in previous studies (Morin et al., 2011b; Ohayon, 2011).