Purpose: To measure self-efficacy in a group of individuals who have undergone a lower-limb amputationand investigate the relationship between self-efficacy and prosthetic-specific outcomes including prostheticuse, mobility, amputation-related problems and global health. A second purpose was to examine ifdifferences exist in outcomes based upon the type of prosthetic knee unit being used.Method: Cross-sectional study using the General Self-Efficacy (GSE) Scale and the Questionnaire forPersons with a Transfemoral Amputation (Q-TFA). Forty-two individuals participated in the study. Twentythreeused a non-microprocessor-controlled prosthetic knee joint (non-MPK) and 19 used a microprocessor-controlled prosthetic knee joint (MPK).Results: The study sample had quite high GSE scores (32/40). GSE scores were significantly correlated tothe Q-TFA prosthetic use, mobility and problem scores. High GSE scores were related to higher levels ofprosthetic use, mobility, global scores and negatively related to problem score. No significant differencewas observed between individuals using a non-MPK versus MPK joints.Conclusions: Individuals with high self-efficacy used their prosthesis to a higher degree and high self-efficacywas related to higher level of mobility, global scores and fewer problems related to the amputationin individuals who have undergone a lower-limb amputation and were using a non-MPK or MPK knee.