Objective. Comparing the clinical effect of flexible ureteroscope and laparoscope in the treatment of parapelvic cyst. Method. A total of 82 patients with parapelvic cyst who underwent surgical treatment in our hospital from May 2019 to May 2020 were selected. Patients were randomly divided into a control group and an observation group; the control group underwent laparoscopic parapelvic cyst topical decompression; the observation group underwent transurethral flexible ureteroscope holmium laser incision and drainage of parapelvic cyst. The intraoperative (operative time, intraoperative blood loss, and ventilation time), postoperative (time of getting out of bed, pain score, and length of hospital stay), and recurrence were compared between the two groups. Results. (1) The operative time and intraoperative blood loss in the observation group were significantly better than those in the control group ( P < 0.05 ), while the ventilation time had no significant difference ( P > 0.05 ). (2) The pain score and length of hospital stay in the observation group were better than those in the control group ( P < 0.05 ). There was no significant difference in the time of getting out of bed ( P > 0.05 ). (3) There was no serious infection or bleeding in either group. The observation group had no recurrence, and the postoperative recurrence rate was 0. There were 11 cases of recurrence in the control group, and the postoperative recurrence rate was 26.83%. The postoperative recurrence rate of the observation group was significantly lower than that of the control group, with statistical significance ( χ 2 = 4.604 , P < 0.05 ). Conclusion. Flexible ureteroscope for the treatment of parapelvic cyst could effectively reduce the operative time, intraoperative blood loss, and pain; in addition, the postoperative recovery was fast and the recurrence is rare, which was worth popularizing.