Objective To investigate the clinical application value of posterior median anal sphincter partial dissection based on external hemorrhoid dissection combined with copper ion electrochemical therapy in the treatment of mixed hemorrhoids. Methods A total of 80 patients with mixed hemorrhoids treated from March 2020 to August 2023 were selected as study subjects, and divided into a control group and an observation group according to the random number table method, with 40 cases in each group. The control group was treated with external hemorrhoid dissection combined with copper ion electrochemical therapy, while the observation group was treated with posterior median anal sphincter partial dissection on the basis of the control group. The anorectal function before and after surgery and recurrence rate were compared between the two groups. Results Before surgery, there were no significant differences between the two groups in maximum anal systolic pressure and resting anal pressure （P>0.05）. One month after surgery, the observation group showed lower levels of maximum anal systolic pressure and resting anal pressure compared to the control group （P<0.05）. The recurrence rate in the observation group （1 case） was lower than that in the control group （8 cases） （P<0.05）. Conclusion On the basis of external hemorrhoid dissection combined with copper ion electrochemical therapy, the use of posterior median anal sphincter partial dissection can effectively improve anal function and reduce the risk of recurrence in patients with mixed hemorrhoids.