Dementia is a progressive cognitive impairment of variable causes. It is considered a global health challenge worldwide as it represents a major comorbidity in the absence of specific treatment or cure. Neurotrophic factors like transforming growth factor β1 (TGFβ1) and brain derived neurotrophic factor (BDNF) have been emerged to be a corner stone in synaptic plasticity and memory. Our work aimed to recognize the potential role of TGFβ1and BDNF in cognitive impairment estimated by the psychometric tests of Alzheimer and multi-infarct dementias. Thirty demented patients divided into two groups (15 in each group) and 25 healthy matched controls were included. Diagnosis of dementia and estimation of psychometric features using modified mini mental state examination (3MS), memory assessment scale (MAS), and beck depression inventory scale were performed. Serum TGFβ1 and BDNF were also assessed in all groups. Psychometric tests revealed significant cognitive impairment in both groups compared to normal control. There was significant increase in the serum level of TGFβ1 and significant decrease in BDNF in both demented groups compared to control group. A significant positive correlation was found between the cognitive impairment and serum TGFβ1 in both demented groups. In conclusion, our findings suggested that serum TGFβ1 levels could reflect the severity of dementia regardless its cause, in addition, depletion of BDNF might be a possible mechanism of cognitive deterioration in dementia.