ABSTRACT Purpose To verify the use of the Frequency Modulation System (FM) and its benefit for cochlear implant users. Methods Analysis of medical records of 113 users of Cochlear Implants (CI) adapted with FM System kits between September 2013 and September 2015 after publication of the Administrative Rule 1.274 of 6/25/2013, regarding the results of the speech perception tests (SPT) and the Listening Inventory For Education - Revised (LIFE-R) and Classroom Participation Questionnaire (CPQ). Results The use of the FM System in the classroom was effective for 47.15% of the patients, while 21.42% did not use it. There was no correlation between the use of the FM System and the age group of patients. The results of the SPT regarding noise were statistically better with the use of FM System. Regarding the questionnaires, the score obtained in the LIFE-R in the situation “after use of the FM System” was statistically better for the item “listening situations in the classroom” and in the CPQ, for the items “teacher understanding” and “positive aspects”, when compared to the situation “without using the FM System”. Conclusion Patients benefitting from the concession of the FM System made use of the device in the classroom and improvement in both speech perception in noisy environments and subjective impression of the understanding of teachers’ speech in the classroom was observed after the use of the FM System.