Robotic hysterectomy may offer advantages for complex cases over the conventional laparoscopic approach. To assess the association of surgical approach (robotic vs conventional) with blood loss, risks of readmission, reoperation, complications, and average operative time. In a retrospective cohort study, we used the electronic medical records of Kaiser Permanente Northern California, 2011 to 2015, to estimate outcomes of robotic and conventional laparoscopic hysterectomy among women with complex or noncomplex benign disease. Mixed-effects regression models accounted for patient characteristics and surgeon volume. The study included 560 robotic and 6785 conventional laparoscopic cases. Overall, 1836 patients (25%) met criteria for being complex. The average operative time was 152 minutes for robotic hysterectomy and 157 minutes for conventional laparoscopic hysterectomy (p < 0.0001). Complex surgical cases averaged 190 minutes and noncomplex cases averaged 144 minutes. The difference in operative time for high-volume surgeons treating complex patients with robotic hysterectomy vs conventional hysterectomy was 21 minutes faster (p < 0.05). After adjustment, the risk of blood loss at least 51 mL was lower for robotic surgery than for conventional surgery for complex and noncomplex patients. Other than risk of urinary tract complications, we observed no differences in the risks of complications or risk of reoperation between robotic and conventional laparoscopy for complex and noncomplex patients. For women with complex disease, the robotic approach, when used by a higher-volume surgeon, may be associated with shorter operative time and slightly less blood loss, but not with lower risk of complications.