The purpose of this study was to examine dental hygienists' knowledge of implant operation, which is recently emerging as one of the important medical services in the dental treatment sector. It's ultimately intended to serve as a basis for the preparation of more effective, appropriate implant-education programs for dental hygienists and to help them, who take a crucial part in implant operation, provide better dental services to patients who are in need of implant operation. The subjects in this study were 368 selected dental hygienists who were working in the dental institutions in the region of Taegu. The results of this study were as below: 1. The largest number of the dental hygienists investigated, 34.1%, were at age 25 to 27. The second most common age was 24 and under, and the third most common age group was 28 to 30. For educational level, most of them, 91.0%, were junior-college graduates, and 9.0% were being in or graduated from four-year-course university. Concerning career, 52.7%, the greatest percentage, had worked for one to three years, and 41.3% had a four-year or higher career. 812%, most of them, were working in dental clinics, and 18.3% were serving in dental hospital or general hospital. 2. Many of the dental institutions were providing implant operation services, as the dental institutions where 64.9% of the subjects were working conducted implant operation. In relation to the necessity of implant operation, the dominant opinion, 73.0%, was thai it's needed to make oral slate healthier. So there was a strong tendency to ad mit implant as one of the necessary treatments in the dental treatment sector. 3. Their collective mean implant knowledge got $57.02{\pm}14.11$. And the collective average of 21 items was $2.7153{\pm}0.6720$ on the basis of 5 points, which was below the average(3 points of Likert scale). This meant that the dental hygienists didn't have a good knowledge or understanding of implant. When it's taken into account what role should be performed by dental hygienists, their implant knowledge should be increased. 4. As a result of examining the effect of the general characteristics on their implant knowledge, the educational level(t=-3.481, P=0.001) and the type of dental institution where they were working(F=16.476, P=0.001) made a significant difference. 5. Their implant knowledge was significantly different according to whether or not the dental institution they were serving conducted implant operation (t=7.199, P=0.001). And, whether or not they agreed to the necessity of implant operation also generated a significant difference to their implant knowledge(F=8.610, P=0.000).