Abstract Purpose: To investigate the effect of cataract extraction on ocular hemodynamics. Setting: University Eye Clinic of Ulm, Germany. Methods: In 51 consecutive patients assigned for cataract surgery, pulse amplitude, pulse volume, and pulsatile ocular blood flow were measured 1 day before and 3 days and 12 months after cataract extraction using an ocular blood flow tonograph. Statistical analysis was performed with Student's t-test and Wilcoxon signed-rank test. Results: In the study eyes, 3 days after cataract surgery pulse amplitude, pulse volume, and pulsatile ocular blood flow had decreased from 2.5 to 2.1 mm Hg (P = .0014), 5.0 to 4.4 µl (P = .0059), and 836.2 to 728.0 µl/min (P = .0017), respectively. No statistically significant change between preoperative and 3 day postoperative measurements occurred in the fellow eyes. There was no significant difference in systemic blood pressure, heart rate, or IOP in study and fellow eyes before and 3 days after cataract surgery. The early reduction of pulse amplitude, pulse volume, and pulsatile ocular blood flow in the study eyes was not present 1 year postoperatively. Conclusion: Uncomplicated cataract extraction is associated with a temporary ipsilateral impairment of ocular hemodynamics. A neural mechanism triggered by cataract extraction may be involved in these temporary changes.