Although social distancing directives are important public health measures to reduce the spread of SARS-cov-2, they can contribute to negative emotional outcomes such as loneliness due to the isolation. Furthermore, individuals have been reporting poorer sleep quality since the beginning of the COVID-19 pandemic. The aim of this study is to investigate the association between loneliness and sleep quality during the COVID-19 confinement. About 136 female participants (Mage = 50.55, SD = 6.0) completed Loneliness Scale, Pittsburg Sleep Quality Index, and a homemade measure of COVID-related worries one week and one month after the confinement measures were established in Quebec, and during the deconfinement period following the first wave of the epidemic. During the first week of confinement, loneliness explained a significant proportion of variance in sleep quality scores, R2=.11, F(4,131)=3.97, p<.01 when controlled for age, chronic health condition, and financial worry due to the pandemic. Sleep quality increased by .215 standard deviations for each standard deviation unit increase in loneliness above and beyond the other variables. However, loneliness did not predict change in sleep quality over time. Therefore, increased loneliness is associated with poorer sleep quality early in the pandemic. The results suggest that increasing social connectedness during periods of confinement may improve sleep quality.