Aim: To examine effects of holistic sleep improvement strategies on frontline nurses who served in Wuhan, China, during a public health emergency (COVID-19). Design: A pre-post-test design with single group was conducted with a convenience sample applied the Transparent Reporting of Evaluations with Non-randomized Designs statement. Methods: Fifty-two nurses were recruited from a COVID-19 designated hospital, receiving holistic sleep improvement intervention, which concentrated on scientific human resource management, comfortable sleep environment establishment, self-relaxation and self-adjustment training and humanistic care. Data was collected at baseline and 4-week follow-up post intervention using self-reported questionnaires. Results: The total score of Pittsburgh Sleep Quality Index scale was 8.69 +/- 4.346 at baseline. After 4 weeks of follow-up, the score statistically significantly decreased to 7.48 +/- 3.691. Subjective sleep quality (p = .016), sleep efficiency (p = .015), sleep disturbances (p = .007) were statistically significantly improved after the intervention, while there were no statistically significant differences in sleep latency (p = .205), sleep duration (p = .375), sleep medication (p = .723) or daytime dysfunction (p = .747).