The Amputee Mobility Predictor (AMP) is an outcome measure designed to assess mobility and functional capabilities for people with unilateral lower-limb amputation. No comparable measure exists for those with bilateral lower-limb amputation (BLLA). The purpose of this study was to examine the utility of the AMP-Bilateral (AMP-B) to measure the ability to perform functional tasks related to participation in advanced skill activities in those with BLLA and to determine whether AMP-B scores correlated with 6-minute walk test (6MWT) performance. Twenty-six male servicemembers (SMs) completed the study: 12 with bilateral transtibial amputation (BTTA), 7 with bilateral transfemoral amputation (BTFA), and 7 with combination transtibial and transfemoral amputation (TTA/TFA). Significant differences existed between the AMP-B scores (p < 0.001), AMP scores (p < 0.001), and 6MWT distance (p < 0.05) for SMs with BTTA and TTA/TFA and SMs with BTTA and BTFA but not between those with BTFA and TTA/TFA. Scoring of five AMP items was modified because they necessitate at least one intact knee joint to generate the necessary torque requirements to perform the activity without upper-limb assistance. Minor modifications in scoring of the AMP do not alter total score and allow clinicians to determine the mobility and functional capabilities of SMs with BTFA and TFA/TTA.