Objective To investigate the relationship between the hearing function and cognitive function in the elderly. Methods A total of 90 veteran cadres older than 60 years living in Shanghai city were divided into 3 groups according to their hearing status: group A (normal hearing), group B (hearing loss with hearing-aid treatment), and group C (hearing loss without treatment), with 30 subjects in each group. Questionnaires and tests including Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Clock Drawing Test (CDT) and Activity of Daily Living (ADL) scale were employed to assess their cognitive function. The cognitive function was compared among the different groups, and its relationship with hearing function was analyzed. Results Cognitive function scores in the 3 groups were described as follow by quartile descriptions in order. MMSE results: 26.00 (22.00, 28.00), 25.00 (21.00, 28.00) and 22.00 (16.00, 24.00); MoCA results: 27.00 (26.00, 28.00), 26.00 (25.00, 27.00) and 22.00 (19.00, 23.00); CDT results: 4.00 (3.50, 4.00), 4.00 (3.00, 4.00) and 2.00 (1.00, 3.00); ADL results: 20.00 (19.75, 21.25), 21.00 (19.50, 24.25) and 24.50 (22.00, 28.00). The nonparametric test showed there were significant differences among the 3 groups (P＜0.001). Significant difference was found between group A and group C (P＜0.001), and group B and group C (P＜0.001). Conclusion Cognitive function is decreased significantly in the elderly with hearing loss without hearing-aid treatment. Hearing disorder is one of important relative factors for cognitive impairment in the elderly. Hearing assistance is beneficial to their cognitive dysfunction.