The aim of this study was to evaluate the effects of modified tongue base suspension (mTBS) procedure on continuous positive airway pressure (CPAP) levels in patients with severe obstructive sleep apnea (OSA). From November 2011 to December 2012, a total of 31 patients with severe OSA who underwent mTBS were included into this prospective case series with planned data collection. Prior to surgery, all the patients were subjected to a polysomnography (PSG) and CPAP titration on two separate nights. Following the surgery, patients were subjected to a control PSG and CPAP titration at the sixth month of follow-up period. The preoperative and postoperative mean apnea hypopnea index (AHI), CPAP titration values, AHI during CPAP use and amount of sleeping time with CPAP were compared. Median age was 48 years (range 31-66), and most patients were male (87.0 %). Postoperative mean AHI (44.73 ± 17.05 vs. 19.96 ± 19.52), optimal CPAP value (12.64 ± 1.60 vs. 8.00 ± 1.77) and AHI during CPAP use (3.79 ± 1.78 vs. 2.25 ± 1.81) were decreased, and the amount of sleeping time with CPAP (5.29 ± 0.84 vs. 6.52 ± 0.89) was increased significantly (p < 0.001 for all parameters). The surgery was considered to be successful when 50 % reduction in the mean AHI and/or the decrease of AHI below 20/h were obtained. A total of 24 patients (77.4 %) met the surgical success criteria. The mTBS is a safe and feasible procedure with favorable effects on CPAP levels in patients with severe OSA.