Objective: Poor sleep quality is common in nursing staff. This meta-analysis aimed to examine the pooled prevalence of poor sleep quality in nursing staff. Methods: A systematic search in PubMed, EMBASE, PsycINFO, and Web of Science databases was performed. Studies that reported sleep quality measured by the Pittsburgh Sleep Quality Index (PSQI) were synthesized using a random-effects model. Results: Fifty-three studies were analyzed. The pooled prevalence of poor sleep quality was 61.0% (95% CI: 55.8–66.1%). The pooled total PSQI score was 7.13 ± 0.18 (95% CI: 6.78–7.50). The pooled component scores were 1.47 ± 0.20 (95% CI of mean score: 1.08–1.85) in sleep latency, 0.91 ± 0.15 (95% CI of mean score: 0.61–1.21) in sleep duration, 1.59 ± 0.13 (95% CI of mean score: 1.35–1.84) in overall sleep disturbances, 0.33 ± 0.18 (95% CI of mean score: 0-0.67) in sleeping medication, 1.21 ± 1.20 (95% CI of mean score: 0.83–1.60) in daytime dysfunction, 1.39 ± 0.14 (95% CI of mean score: 1.11–1.67) in subjective sleep quality, and 0.66 ± 0.11 (95% CI of mean score: 0.44–0.87) in habitual sleep efficiency. Subgroup and meta-regression analyses found that PSQI cutoff values, mean age, body mass index (BMI), sample size, study quality, and work experience moderated the prevalence of poor sleep quality. Conclusions: Poor sleep quality appears to be common in nursing staff. Considering its negative impact on health, effective measures should be taken to improve poor sleep quality in this population. Longitudinal studies should be conducted to examine the contributing factors of nurses’ poor sleep quality.