Introduction: The purpose of the current study was to test the theory that elderly patients undergoing laparoscopic rectal cancer surgery have impaired microvascular perfusion, which recovers following the administration of phenylephrine and ephedrine. Material and Methods: Patients were divided into one of the two groups using a random number sheet produced by computer software. Anesthetist sealed the opaque envelope with the random number sheet before starting the clinical trial. Ephedrine and N/S were infused into the patients in two different groups. Results: At the time of the phenylephrine injection, the microvascular flow index in the phenylephrine group decreased from 2.89 ±0.16 at baseline to 1.85 ±0.36. At the same time, the number of perfused vessels decreased from 99.16 ±1.74 percent to 64.02± 16.05 percent, and the density of perfused vessels decreased from 16.33± 4.24 mm/mm2 to 10point videos of the sublingual microcirculation''s sidestream dark field images. Three images of the patients'' baseline states, 10 min after anesthesia induction, and 5 min after ephedrine administration have been provided. Images for the phenylephrine group at the same time points have also been provided. Conclusion: MAP decline and sublingual microcirculation changes were observed in elderly patients undergoing laparoscopic surgery for rectal cancer. With the help of phenylephrine and ephedrine, sublingual microcirculation was successfully recovered.