This study aimed to assess the overall level of sleep quality among female staff nurses in the United States during the early COVID-19 pandemic. It also aimed to examine factors associated with sleep quality and its seven subcomponents: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbance, use of sleeping medications, and daytime dysfunction. A descriptive, correlational, and cross-sectional study design was used. We performed descriptive, and regression analyses with a sample of 215 female staff nurses enrolled in post-licensure online nursing programs at a southeastern state university. Data collection was conducted using an online survey from April to May 2020. Sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI). Nurses working part time (p = 0.02), with lower perceived physical health (p = 0.01), a lower self-care self-regulation score (p < 0.001), and higher work stress (p < 0.05) showed poorer sleep quality. Factors associated with subcomponents of sleep quality varied. Poor sleep quality among nurses during the COVID-19 pandemic was reported. Various factors, including work environmental factors were associated with the sleep quality in this sample. Hospital administrators should consider developing intervention programs for improving the work environment, which would impact sleep quality, health status, and job performance.