The increase in life expectancy observed over the last decade has particular relevance for conditions such as cognitive decline and dementia.This is a cross sectional study to determine the prevalence of cognitive impairment and dementia and to identify its associated factors among 399 elderly patients in Hospital Universiti Sains Malaysia.This study was conducted in 2 phases. In the first phase, subjects were screened using either validated Malay version of Mini Mental State Examination (MMSE) or Elderly Cognitive Assessment Questionnaire (ECAQ). All subjects suspected to have dementia were selected for further evaluation in phase 2 of this study. The second phase involved full clinical examination to establish the diagnosis of dementia. The prevalence of cognitive impairment and dementia in this study was 11.8% and 2.5% respectively. The result showed that the predictors for occurrence of cognitive impairment were female sex (p<0.05), non educated subjects (p<0.05), number of living 8 and above (p<0.05) and history of hypertension (p<0.05). History of exposure to pesticide (p<0.05) and history of stroke (p<0.05) were significantly associated with dementia.