Objective: To analyze duties, tasks, and task elements of health workers in charge of vaccination at public health centers in South Korea. Design: Descriptive study using a survey. Sample: Health workers in charge of vaccination for more than 1 year at 254 public health centers in South Korea. Of 631 health workers, 401 responded to the questionnaire, and 379 responses were included in the analysis after excluding 22 incomplete responses. Measurements: The Developing A Curriculum (DACUM) workshop was conducted to identify the frequency, importance, and difficulty of duties, tasks, and task elements. Results: Four duties (vaccination promotion, vaccination administration and symptom management, execution of vaccination, and vaccination education), 18 tasks, and 81 task elements were identified. “Execution of vaccination” exhibited the highest determinant coefficient. “Implementing the budget” exhibited the highest determinant coefficient among tasks, and “dealing with an emergency in the case of adverse events” exhibited the highest determinant coefficient among task elements. Conclusions: Duty, task, and task elements with high determinant coefficients have high educational needs. Education demands was higher for administrative work than for direct vaccination. Developing an educational curriculum based on DACUM results could contribute to the professional education of vaccine workers.