There are many non-cognitive behaviors in dementia such as delusion, hallucination, mood, sleep, sexuality, agitated behavior etc. Some differences exist in the behaviors according to the type of dementia. Different types of neuropsychiatric disturbances have been linked to specific brain diseases and anatomical region. Some studies suggest that the neuropsychiatric disturbances are not highly correlated with particular neuropsychological deficits and are best conceptualized as manifestations of CNS dysfunction rather than as reaction to declining intellectual abilities. Sometimes neuropsychiatric changes antedate the cognitive decline, and are presenting manifestation of the dementia. This paper reviews the characteristics of non-cognitive behaviors in several types of dementia.