Background: Surgery is the main line of treatment of endometriosis. Patients with stage IV endometriosis have more extensive adhesions, which make the surgery difficult. There are no accurate non-invasive predictive preoperative parameters of stage IV endometriosis and no consensus has been reached. Therefore, the aim of the present study was to evaluate and detect preoperative non-invasive parameters for the detection of stage IV endometriosis. Patients and methods: In the present study, we included 150 females admitted for surgical removal of endometriosis. We scored and classified endometriosis into four stages according to the revised ASRM classification. We compared between baseline characteristics of patients with different stages of endometriosis, and then we selected the best combination of diagnostic and predictive parameters of stage IV endometriosis. Results: Predictors of stage IV endometriosis and indicators for safety surgery were as follows: VAS ≥ 4 (p < 0.001), fixed uterus (p = 0.005), fixed ovarian cysts (p < 0.001), tender uterosacral ligament nodule (p < 0.001), tender rectovaginal septum nodule (p = 0.003), bilateral endometriosis (p < 0.001), and sum of sizes of endometriotic nodules (p < 0.001). Conclusion: Fixed uterus, fixed ovarian cysts, tender uterosacral ligament nodule, tender rectovaginal septum nodule, bilateral endometriosis, and indications for surgery were significantly considered adequate predictive markers for stage IV endometriosis. [ABSTRACT FROM AUTHOR]