A 70-year-old female, herdsman from Gonghe County, Qinghai Province, was presented to Department of General Surgery, Qinghai Provincial People’s Hospital on November 8, 2025, with complaints of lower abdominal pain and discomfort for 2 years and aggravation for 4 days. The patient has a clear history of long-term residence in a pastoral area. Abdominal and pelvic CT scans displayed a massive cystic mass in the abdomen and pelvis, containing multiple daughter cysts and band-shaped high-density shadows, with the largest cross-sectional dimension measuring approximately 225 mm × 85 mm, compression of the right ureter and hydronephrosis, gallstones and a cyst in the left kidney. Color doppler ultrasound of the pelvis showed a cystic mass measuring approximately 225 mm × 85 mm from the xiphoid process to the pelvic cavity, and the mass displayed clear borders and contained multiple daughter cysts with a “cabbage-like” appearance. Admission diagnosis included intraabdominal echinococcosis, urinary tract infection and chronic hepatitis B. The case was given exploratory laparotomy, complete excision of Echinococcus cysts and adhesiolysis of pelvic adhesions under general anesthesia on November 13, 2025, based on imaging findings and clinical symptoms. Intraoperative findings included a massive cystic mass in the abdominal and pelvic cavities, measuring approximately 22 cm × 8 cm, with thick, milky-white walls. Exploration revealed that the pedicle of the mass originated from the right ovary, and the main body of the cyst extended upward into the upper abdomen and was firmly adherent to the greater omentum, the inferior margin of the liver, the right kidney, and the right ureter, with the uterus and left adnexa appearing normal. Right ovarian echinococcosis was diagnosed intraoperatively, and cystectomy of right ovarian echinococcal cysts was performed. Following postoperative pathological examinations, right ovarian echinococcosis was confirmed. The patient recovered well postoperatively and was discharged from hospital 9 days post-operation. The patient was instructed to take albendazole (200 mg/dose, twice daily) regularly after discharge and to undergo periodical follow-up with color Doppler ultrasound of the liver, gallbladder, pancreas, and spleen, as well as liver function tests. No recurrence or surgery-related complications have been recorded until now.