Objectives: In this study, we aimed to examine the dysphagia knowledge, preventive attitudes toward dysphagia, and educational needs concerning geriatric oral health, of dental hygienists, and to provide fundamental information for recognizing the necessity of knowledge and education concerning geriatric oral health and for increasing educational needs. Methods: From April 1 to June 30, 2022, a questionnaire survey was administered to 198 dental hygienists via an online link. SPSS Statistics ver. 22.0 was used to conduct the frequency analysis, t-test, one-way ANOVA, Pearson’s correlation coefficient, and multiple regression analysis. Results: Regarding the difference in knowledge of dysphagia depending on general characteristics, the study participants had more knowledge of dysphagia when they were more interested in dysphagia and had a higher geriatric treatment frequency. The preventive attitudes toward dysphagia were strong in those who graduated from graduate school or higher, had more prevention and education at work, became more interested in dysphagia, received more education about dysphagia, had intention to receive additional education on dysphagia, and had a higher geriatric treatment frequency. Positive correlations were observed between knowledge of dysphagia, preventive attitudes toward dysphagia, and educational needs related to geriatric oral health. The educational needs related to geriatric oral health were found to be, significantly and positively influenced by preventive attitudes toward dysphagia, having master’s degree or higher, knowledge of dysphagia, and intention to receive additional education on dysphagia. Conclusions: It is necessary to improve the quality of oral health services offered to older patients by having accurate knowledge of dysphagia implementing appropriate prevention practices for dysphagia, and understanding the educational content needed by the oral hygienists and developing an effective education program to enhance their professionalism.