Impingement of the common peroneal nerve, a branch of the L5 nerve root, causes common peroneal nerve entrapment neuropathy (CPNE). Although there are cases of CPNE associated with L5 radiculopathy, surgical intervention's effectiveness remains to be elucidated. This retrospective case-control study aimed to evaluate the efficacy of surgery in patients with CPNE associated with L5 radiculopathy. Twenty-two patients (25 limbs) with surgically treated CPNE between 2015 and 2022 were retrospectively reviewed. The limbs were classified into two groups: group R (limbs of CPNE associated with L5 radiculopathy) and group O (limbs of CPNE without L5 radiculopathy). The durations from onset to surgery, the nerve conduction studies (NCSs), and postoperative improvement rates for motor weakness, pain, and dysesthesia were compared between the groups. Group R included 15 limbs (13 patients), and group O included 10 limbs (9 patients). There were no significant differences in the duration from onset to surgery or abnormal findings of NCS between the two groups. The postoperative improvement rates were 88% and 100% (p = 0.62) for muscle weakness, 87% and 80% (p = 0.53) for pain, and 71% and 56% (p = 0.37) for dysesthesia in group R and group O, respectively, without significant differences between groups. CPNE associated with L5 radiculopathy is common, and the results of the present study showed that the surgical outcomes in such cases were satisfactory and comparable to those in CPNE without L5 radiculopathy.