The objective was to asses the feasibility of the endoscopic technique for cochlear implant (CI) positioning avoiding mastoidectomy and to discuss the benefits and drawbacks of the technique. The study design is a surgical procedure description and prospective case series report. From December 2011 to October 2012, six patients underwent endoscopic CI. All cases were selected based on CT and MRI studies. All surgical steps were analyzed; intra-and post-operative complications were noted. The length of time for each surgical procedure was recorded. The surgical procedure was described step by step focusing on the anatomy of the round window (RW) niche, analyzing the critical point during the dissection. The timing of the surgical procedures was 120 ± 21 (mean ± SD) min. In 1/6 patients, intra-operative injury of the chorda tympani occurred. In all cases, an endoscopic identification was performed and the anatomical details of the RW niche were noted. In 6/6 cases, a RW niche magnification was performed endoscopically. 5/6 cases showed a normal conformation of the RW. In 1/6 patients, obliteration of the RW niche was found. In 4/6 patients, an endoscopic cochleostomy through the RW was performed. In 1/6 patients, a difficult insertion of the array was observed. The current follow-up is 7.3 months (SD ± 3.7). No post-operative short- or long-term complications were noted in this series. Endoscopic CI is a safe and viable technique with a low rate of complications and with good outcomes.