To investigate the correlation between the levels of the preoperative systemic immune inflammation (SII) and matrix metalloproteinase-9 (MMP-9) of women with endometriosis (EMs) and their postoperative recurrence of EMs. Methods: 80 women with EMs who wanted laparoscopic surgery were selected in study group, and 80 healthy women of childbearing age who wanted the physical examination were selected in control group from January 2019 to January 2020. The levels of the serum SII, MMP-9 and carbohydrate antigen (CA) 12-5 of the patients were compared between the two groups, and the clinical values of which for predicting the postoperative recurrence of EMs of the patients were analyzed. Results: The recurrence rate of EMs of the patients in the study group was 13.8% during 24 months of the follow-up. The levels of the preoperative serum SII ［415.24 (291.81-573.09) and M(P25,P75)］ and MMP-9 (229.65±66.34μg/L) of the patients in the study group were significantly higher than those ［326.55 (249.74-381.62) and M(P25,P75), and (160.78±42.15μg/L)］ of the patients in the control group, and which of the patients with the recurrence of EMs were all significantly higher than those of the patients without the recurrence of EMs, and which of the patients with the r-AFS Ⅲ-Ⅳ of EMs were also significantly higher than those of the patients with the r-AFS Ⅰ-Ⅱ of EMs (all P<0.05). Spearman correlation coefficient analysis showed that the preoperative serum SII and MMP-9 levels of the patients with EMs were positively correlated with their postoperative recurrence of EMs (P<0.05). The area under the curve (0.874) of the combination of the preoperative serum SII and MMP-9 levels of the patients with EMs for predicting their postoperative recurrence of EMs was significantly higher than that (0.825) of the SII level or that (0.767) of the MMP-9 level alone, and the specificity of which was 91.3%. Conclusion: The patients with EMs and the higher levels of the preoperative serum SII and MMP-9 have the higher risk of the postoperative recurrence of EMs. The combination of the preoperative serum SII and MMP-9 levels of the patients with EMs for predicting their postoperative recurrence of EMs has some value for the clinical guidance.