Background: researchers came to agreement on that bipolar disorder is commonly linked to impairment in cognitive functions by a remarkable degree. More and more evidence continue to support that the cognitive impairment remains persistent even within euthymic periods which in turn points to cognitive impairment as a possible characteristic of the disorder. Aim of the Work: objective assessment of bipolar patients' cognitive deficits present during remission and holding a Comparison of these deficits with control subjects who are completely healthy. Patients and Methods: assessing cognitive functions including executive functions, attention and memory in euthymic bipolar patients by using relevant scales, then using SPSS for comparing the results with those of a control group. Results: when compared to healthy control subjects, euthymic bipolar patients were found to exhibit a markedly noticeable impairment in attention, executive functions and total memory score. It was also noteworthy that the association between the duration of illness demonstrated through the number of episodes and the extent of impairment in cognitive functions. Conclusion: there is an apparent association of bipolar disorder with cognitive impairment even when patients are in euthymic state and consequently, the number of episodes increases the impairment degree.