Objective To investigate the oral hygiene status of elderly inpatients and analyze its influencing factors. Methods Totally 312 elderly patients admitted between January 2021 and June 2022 in General Hospital of Central Theater Command were enrolled as the research subjects. Kayser-Jones brief oral health status examination (BOHSE) was used to investigate the oral hygiene status (10 items including lymph node, lips, tongue, mucosa of cheek/floor of mouth and maxilla, gingiva around the teeth and (or) covered by dentures, salivary secretion and its effect on tissues, natural teeth status, denture status, dental occlusion status at masticatory position, oral hygiene status). SPSS statistics 20.0 was used for statistical analysis. Data comparison between two groups was perfomed using t test, analysis of variance or χ² test depending on data type. Multivariate linear regression analysis was used to analyze the related influencing factors of oral hygiene status of elderly inpatients. Results Investigation showed that the total score of BOHSE scale in elderly inpatients was (7.91±1.27) points, and the score of oral hygiene status dimension was the highest at (1.46±0.26) points, followed by the natural teeth status and gingiva around the teeth and (or) covered by dentures. Univariate analysis showed that gender, smoking, drinking, education level, frequency of teeth brushing during hospitalization, access to oral care assistance during hospitalization, oral examination, previous oral hygiene behaviors, activities of daily living and long-term bed rest were related factors affecting the oral hygiene status of elderly inpatients (P<0.05). Multivariate linear regression analysis suggested that gender, smoking, drinking, frequency of teeth brushing during hospitalization, access to oral care assistance, oral examination, previous oral hygiene behaviors, activities of daily living and long-term bed rest were related factors affecting the oral hygiene status of elderly inpatients(β =-3.784,1.757,1.123, -0.892, -0.971, -1.343, 1.834,2.156,4.254; P<0.05). Conclusion The overall oral hygiene status of elderly inpatients is not good. It is necessary to pay clinical attention to the oral hygiene status of patients with low activities of daily living and long-term bed rest. It is of certain significance to improve the oral hygiene status of elderly inpatients by persuading patients to quit smoking and drinking, providing more oral care assistance and strengthening oral examination.