Recurrent/residual adenoidal hypertrophy after adenotonsillectomy in children can result in obstructive sleep apnea (OSA). We aimed to assess the polysomnographic (PSG) outcomes of revision adenoidectomy in children with recurrent/residual adenoidal hypertrophy and OSA. This was a single-center retrospective study that included children with sleep studies that confirmed OSA and known history of adenotonsillectomy who were diagnosed with adenoidal hypertrophy and subsequently underwent revision adenoidectomy. Pre- and postoperative PSG variables of revision adenoidectomy were included in the analysis. A total of 20 children were included in the study. The cohort included 13 males and 7 females with a mean age of 7.8 years (± 3.6 years). The mean BMI z score was 1.96 [1.31, 2.43]. The median duration from adenotonsillectomy performance was 2.3 years [1.4, 4.0]. Overall, revision adenoidectomy resulted in significant improvements in multiple respiratory parameters, including AHI 6.6 [1.4, 13. 7] vs 14.8 [7.4, 20.7], p = 0.02; oxygen desaturations nadir 88.0 [84.0, 93.0] vs 80.0 [72.2, 88.9], p = 0.01; supine AHI 8.6 [1.5, 14.3] vs 17.6 [8.3, 30.2], p = 0.02; and arousal index 12.2 [9.6, 15.7] vs 18.9 [13.4, 24.9], p = 0.04. Children with recurrent/residual adenoidal hypertrophy after adenotonsillectomy who undergo revision adenoidectomy experience improvements in respiratory event, gas exchange, and arousal index.