Background: Systemic lupus erythematosus (SLE), a diverse autoimmune inflammatory condition, affects various organs and systems. Determining the origin of sleep disturbances in systemic lupus erythematosus patients is essential to create specific and focused measures to enhance sleep quality. Objective: This study aimed to evaluate the sleep quality of a group of patients with systemic lupus erythematosus and investigate the correlation between sleep quality and disease activity, severity, and different disease parameters. Patients and methods: The present cross-sectional study included 73 systemic lupus erythematosus patients. Disease activity was assessed by means of the Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K). SLE severity was assessed by the SLICC/ACR damage index. Life quality was assessed by the short form quality of life (SF-36 QoL) scale. Assessment of sleep disturbances was conducted using the Pittsburgh Sleep Quality Index (PSQI). Results: Patients with lower PSQI (21) scores showed significantly higher SLEDAI scores, indicating a more active disease compared to those with higher scores (p=0.001). Lower scores were associated with significantly greater SLICCs scores, indicating a more severe disease state (p=0.008). Patients with good PSQI 21 scores had slightly higher SF36 scores (mean=60.58) than those with poor scores (mean=54.11), nevertheless, the disparity did not exhibit statistical significance (p=0.071). Conclusion: Systemic lupus erythematosus patients often suffer from poor sleep quality. Disease features and sleep variables impact sleep quality. Poor sleep may negatively impact systemic lupus erythematosus patients' disease activity, damage, as well as well-being.