Gait is a complicated motor task controlled by different areas of the brain. Epidemiological studies show that gait is closely associated with cognitive function in the elderly. Older adults with gait impairment are of higher risk for developing cognitive impairments. Compared with normal healthy old people, those with cognitive impairment show more preference to have gait impairments, and are more prone to falling. Cognition and gait, which may have a mutual relationship, may occur in the same area of the brain. So, better overall gait is related to better overall cognitive function. In recent years, many abroad researches demonstrated that stride speed and stride-to-stride variability of stride time (STV) are predictors of cognitive impairment. However, there are few such researches in China. This article reviewed the new progress in the studies concerning walking speed and STV with cognitive impairment, and aimed at raising awareness of clinicians on this subject. We need to conduct neuropsychological tests based on the elderly gait in order to detect cognitive impairment as early as possible.