Objective: Elderly people with dementia experience not only cognitive dysfunction but also motor function deficits, such as balance and gait impairments. Recently, transcutaneous electrical nerve stimulation (TENS) has been used to reduce pain as well as to control muscle spasm, spasticity and motor performance in various types of subjects. The purpose of this study determined the effect of a single trial TENS on balance and gait function in elderly people with dementia. Design: A randomized controlled trial. Methods: Twenty-two subjects with dementia were assigned to the TENS group (n=12) and ten subjects were assigned to the control group (n=10) randomly. Subjects were classified into two groups: the TENS group (n=12) and the placebo-TENS group (n=10). The TENS group had electrical stimulation applied on the calf muscle for 15 minutes, while the placebo-TENS group had not received real electrical stimulation. The timed up and go test (TUG) and functional reach test (FRT) were used to measure the balance function, and the 10 meters walk test (MWT) and 6MWT were used to assess gait ability. All tests were performed before and after intervention under a single-blinded condition. Results: After intervention, there were significant improvements in TUG, FRT, 10MWT, and 6MWT results in the TENS group (p<0.05), while the placebo-TENS group did not show significant changes in all outcome measurements. There were also differences in all tests between the two groups at post-measurements (p<0.05). Conclusions: This study demonstrated that a single trial TENS application on the calf may be used to improve balance and gait function in elderly people with dementia.