Introduction The COVID-19 pandemic resulted in an unpredictable healthcare crisis with a high psychological burden on healthcare workers. Objective To evaluate burnout levels and their associated demographics and occupational factors among intensive care unit healthcare workers during the COVID-19 pandemic in a single hospital in the city of Temuco, Chile. Methods A cross-sectional design in which a sociodemographic questionnaire and the Maslach Burnout Inventory for Human Services were sent to health care workers in a single Chilean Intensive Care Unit during the pandemic COVID-19. Burnout levels, demographic, and occupational factors are reported using descriptive statistics; correlations between burnout levels and demographic-occupational factors were analyzed using Spearman’s and rankbiserial correlation coefficients; and multiple linear stepwise regression was used to assess the contribution of demographic and occupational factors to participants’ burnout levels. Results A total of 84 participants (46 women and 38 men) were included in the analysis. Depersonalization and low personal accomplishment were evidenced in 95.2% and 98.8% of the intensive care unit healthcare workers, respectively. Emotional exhaustion was positively correlated with having children (r = 0.72; p < 0.01). Age (r = 0.79; p < 0.05), sex (r = 0.30; p < 0.05), and prior experience in intensive care unit facilities (r = 0.71; p < 0.05) were correlated with depersonalization. Feeling of personal accomplishment was positively correlated with with sex (r = 0.70; p < 0.05) and type of work shift (r = 0.29; p < 0.01). Conclusions The intensive care unit healthcare workers in this study reported high levels of depersonalization and low feelings of personal accomplishment during an advanced stage of the COVID-19 pandemic. Older age, being female, having children, having intensive care unit experience, and working at 4th shift were factors related to burnout dimensions.