The aim of the study was to determine whether cavernous nerve preservation in men with prostate cancer and preoperative poor erectile function is a worthwhile endeavor. This is a retrospective analysis of prospectively collected data of 1,160 patients comparing erectile function pre- and postoperatively with 2 years of follow-up. Sexual Health Inventory for Men–International Index of Erectile Function 5 (SHIM-IIEF-5) questionnaire was used for assessment of erectile dysfunction preoperatively and at 6, 12, and 24 months postoperatively. IIEF < 13 was considered for inclusion. Bilateral nerve-sparing (BNS, n = 33) versus non-nerve-sparing (NNS, n = 32) procedures were compared. Continence data was collected. All men were offered penile rehabilitation therapy. Average preoperative IIEF-5 scores were 5.45 (BNS) and 4.28 (NNS) and not statistically significant. At 2 years, the average post-op IIEF scores were 4.91 (BNS) and 2.06 (NNS). This was a statistically significant decline in the NNS group. Most erectile function was recovered by 1 year. Positive surgical margins were not statistically significant between groups. Continence was improved in the BNS group (78 vs. 50 %, p = 0.047). Nerve sparing appears to be a worthwhile endeavor in men with poor preoperative IIEF as they return to baseline, oncologic outcomes are not compromised, and may have a continence benefit. The decision for an NNS procedure should not be made on the patient’s preoperative erectile function, but on the merits of other indicators such as grade or advanced clinical stage.