Abstract Introduction Shift work is associated with insufficient and disrupted sleep and impaired quality of life due to misalignment between the timing of internal biological clock and work/sleep schedule. There are reported sex differences in the circadian timing system, in sleep, and in reported sleep complaints, but how these impact female shift workers remains unclear. Furthermore, relatively little is known about sex differences in quality of life in shift workers. The objective of this study is to investigate sex differences in sleepiness, insomnia and quality of life in healthcare shift workers. Methods Forty women (31 ± 6.4 yo) and 70 men (31.2 ± 6.7 yo) who work at least 4 night shifts a month, completed the Shift Worker Sleep and Health Survey. This REDcap administered survey included the Epworth Sleepiness Scale (ESS), Insomnia Severity Index (ISI), and Functional Outcomes of Sleep Questionnaire (FOSQ-10). Independent samples T-tests were carried out using SAS. Results Women reported significantly higher scores on the ESS compared to men (13 ± 4 vs. 11 ± 3.4, respectively; t(108)=-2.74,P=0.007), as on the ISI (13 ± 5.2 vs. 9.8 ± 5.4; t(108)=-3.05,P=0.003), indicating greater levels of daytime sleepiness and insomnia-like symptoms in female shift workers. In addition, women scored significantly lower on the FOSQ-10 than men (13.9 ± 2.9 vs. 15.3 ± 2.5; t(108)=2.68,P=0.009), suggesting a lower functional status related to activities of daily living in female shift workers. Conclusion These preliminary analyses suggest that in this group of healthcare shift workers, women are less tolerant to irregular work hours compared to men, in terms of sleep, sleepiness and quality of life. Our future goal is to understand how sleep quality and duration, daytime sleepiness, and quality of life interact, and what role sex plays in those interactions. Support The study was supported by NIH grant R01 AG044416.