Background: MicroRNAs (miRNAs) contribute to the development and progression of systemic lupus erythematosus (SLE) by affecting a wide range of targeted genes and facilitating the development of lupus nephritis (LN). The present study aimed to analyze the serum expression of miR-181a and miR-223 in SLE patients and to assess whether they could serve as novel biomarkers for SLE diagnosis and to distinguish LN. Methods: The study included 70 control subjects and 116 patients with SLE (67 non- LN and 49 LN groups). Circulating miR-181a and miR-223 expression levels were analyzed among the Egyptian population using a real-time polymerase chain reaction. Results: Up-regulation of miR-181a was detected among SLE patients compared to healthy controls and higher values were reported among the LN group compared to the non-LN group. Down-regulation of miR-223 was reported among SLE patients compared to controls and lower values were reported among the LN group compared to the non-LN group. The higher miR-181a expression and the lower miR-223 expression were associated with higher stages of LN. SLE disease activity index, pro- teinuria and serum creatinine were independently correlated with miR-181a and miR-223 among SLE patients by linear regression analysis. Receiver-operating char- acteristic curve analysis revealed that combined miR-181a and miR-223 expression increased the sensitivity and specificity for the diagnosis of SLE and further distin- guished LN from non-LN patients. Conclusions: miR-181a and miR-223 could play a role in evaluating SLE disease pro- gression and prognosis. Combined miR-181a and miR-223 expression analysis could serve as novel serum-based biomark