This study sought to identify whether the inter-rater reliability of lower limb muscle strength measurements made using a hand-held dynamometer differs for patients with hip fracture according to the severity of their cognitive impairment. Of the 144 patients with hip fracture hospitalized at our institution, we excluded 28 from this study (18 with level III, IV, or M of independence in daily living for the demented elderly, 8 with a history of central nervous system disorders, and 2 who were transferred to another department), leaving 116 patients for analysis. These 116 patients were divided into three groups according to their severity of cognitive impairment: 44 with a normal level of independence in daily living for the demented elderly, 38 with level I independence, and 34 with level II independence. We compared the intra-class correlation coefficients and the standard error of measurement between the groups. There were no significant differences in the intra-class correlation coefficients between the groups. The standard error of measurement in the group with level II independence in daily living for the demented elderly was significantly lower than that in the other two groups. These findings indicate that the inter-rater reliability of lower limb muscle strength measurements using a hand-held dynamometer in patients with hip fracture did not differ between patients with mild or moderate cognitive impairment. Furthermore, the inter-rater reliability was high.