Approximately 40%-60% of all amputations are lower limb amputations (LLAs) related to diabetes mellitus (DM). The importance of quality of life (QoL) is increasingly recognized as after amputation. The objective of this cross-sectional study was to compare QoL (evaluated by Berg Balance Scale, BBS) in DM patients with unilateral transtibial amputation (TTA) using prosthesis (group A) with that of patients amputated due to other causes (group B). Overall, 32 patients completed two questionnaires: the 36-Item Health Survey (SF - 36) for QoL assessment and the Trinity Amputation and Prosthesis Experience Scale-Revised (TAPES-R). In group A, patients were significantly older ( P < .05) with shorter periods of prosthesis use ( P < .05) and had significantly lower ( P = .008) adjustment to limitation (TAPES-R). Correlations were found between BBS score and SF-36, including physical functioning ( P < .001, r = 0.682), energy and fatigue ( P < .001, r = 0.643) and emotional well-being ( P < .001, r = 0.644). In the TAPES-R, a large negative correlation was found between BBS and activity restriction ( P = .001, r = -0.595). Poorer balance ability, greater activity limitation, and worse psychosocial adjustment to the prosthesis were found in patients with unilateral TTA and DM compared to TTA prosthesis users without DM.