ObjectiveTo investigate the relationship between sleep quality and mild cognitive impairment(MCI) in elderly patients with type 2 diabetes mellitus(T2DM).MethodsWe collected 97 elderly patients with type 2 diabetes mellitus and divided them into two groups: MCI group (DM-MIC) and normal cognition group (DM-NC group). All subjects were evaluated with cognition scores of Mini-mental state examination (MMSE), Montreal Cognitive Assessment (MOCA),Self-Rating Anxiety Scale(SAS),Center for Epidemiogical Studies Depression Scale(CES-D), Activity of daily living(ADL), Global Deterioration Scale(GDS), and Pittsburgh sleep quality index(PSQI). Independent t-test and Spearman’s rank correlation analysis were performed.ResultsThe hypnotic use in DM-MCI group was significantly more than that in DM-NC group (P=0.046), and it had a negative correlation with the score of delayed recall, but not statistically significant(r=-0.277, P=0.062). Significantly negative correlations were also found between the score of PSQI and MOCA (r=-0.362), PSQI and attention(r=-0.319), PSQI and delayed recall(r=-0.409), daytime dysfunction and MOCA(r=-0.393), daytime dysfunction and abstraction(r=-0.337), night sleep disorders and language(r=-0.439), sleep efficiency and delayed recall(r=-0.325), and subjective sleep quality and delayed recall(r=-0.336) in DM-MCI group(P<0.05).ConclusionSleep quality is correlated with some symptoms of mild cognitive impairment in elderly patients with T2DM.