This study aimed at examining the differences in leg strength and activities of daily living (ADL) ability among groups with various knee problems. The subjects consisted of 328 elderly females who were classified into three groups: those without knee pain or a knee disorder, those with knee pain, and those with a knee disorder. The subjects took a knee extension strength test and an ADL survey. Knee extension strength and ADL scores (total score and each domain score of the motions of locomotion, posture change, stability, and manipulation) were selected as the evaluation parameters. The knee extension strength, total ADL score and each domain score of the motions of locomotion, posture change, and stability ranged from low to high in the following order: the group with a knee disorder, the group with knee pain, and the group without pain or a knee disorder. Moreover, manipulation scores were significantly inferior in the group with a knee disorder compared with the other two groups. In conclusion, the female elderly with knee pain or a knee disorder have inferior knee extension strength and ADL with respect to the motions of locomotion, posture change and stability. In addition, with regard toknee extension strength with respect to theabove three motions, the elderly with a knee disorder have inferior scores when compared with the elderly who have only knee pain; thus, they find it difficult to perform activities involving the knee joints.