This study aims to characterize the hearing benefits and sound localization accuracy of bilateral adhesive bone conduction devices (aBCDs) compared to unilateral devices in patients with congenital bilateral conductive hearing loss (BCHL).Sixteen children and adolescents with congenital BCHL were enrolled and tested under four listening conditions: (1) unaided, (2) R aided: aided with a right-side aBCD, (3) L aided: aided with a left-side aBCD, and (4) B aided: aided with aBCDs on both sides. The sound field hearing threshold (SFHT, in dB hearing level [HL]) and the word recognition score (WRS) were measured. The mean absolute error (MAE) of sound source localization was calculated to assess the sound localization accuracy.The performance in SFHT and WRS was significantly higher in the B aided condition than that in the unaided, R and L aided conditions; moreover, no significant difference was observed between the R and L aided conditions. Concerning sound source localization, the accuracy of localization exhibited a sharp decline when using a single aBCD, while the application of bilateral aBCDs (B aided condition) resulted in a significantly improved localization accuracy as compared to the unilaterally aided conditions (both R and L); however, no significant difference was found between the unaided and B aided condition.Patients with congenital BCHL experienced suboptimal hearing benefits and manifested significant challenges in sound source localization when utilizing a single aBCD, as compared to the utilization of bilateral aBCDs.Copyright © 2023. Published by Elsevier Inc.