To improve our understanding of systemic lupus erythematosus (SLE)-macrophage activation syndrome (MAS). A systematic review was performed, to retrieve all those papers on patients with SLE-MAS, in individual or aggregated form. The data in each of these medical records were extracted and analyzed to identify the characteristics of SLE-MAS. A total of 86 SLE-MAS patients were included (25 males and 61 females. The mean (±standard error of the mean) age was 31.21 ± 1.694 years. MAS occurred as the initial presentation of SLE in 47 people (54.65%) and during the course of SLE in 39 (45.35%). A coinfection was reported in 23 (26.74%) patients. The mean Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score was 16.54 ± 0.9462. Overall, 10 patients (11.63%) died. The SLEDAI-2K score was higher in patients with MAS as an initial manifestation of SLE than in those where MAS occurred during the course of SLE. The proportion of patients receiving steroid pulse therapy was lower in patients with coinfections. The deceased group demonstrated lower platelet and ferritin levels. Multiple regression analysis revealed that age and thrombocytopenia were independent factors associated with poor prognosis. In receiver operating characteristic analysis, a platelet count cutoff value of ≤47 × 109/L was a predictor of poor outcome. SLE-MAS patients demonstrated high lupus activity, and lupus activity was especially higher in patients with MAS as an initial manifestation. Lupus activity was the predominant trigger of lupus MAS. Thrombocytopenia was an independent factor for poor prognosis.