This study was performed to identify the occupational diseases in the dental technicians working in Korea, and to elucidate the main related affecting factors for the occurrence of the occupational diseases. The research was carried out using a mail questionnaire and data collection was done for two months from April 15, 2000. The questionnaires were delivered to 1000 dental technicians working at 250 dental laboratories which were chosen among the total 1330 dental laboratories in south Korea. And 763 questionnaires were collected, then 739 questionnaires were used for a logistic and a multiple regression analyses. The results obtained in this study are summarized as follows: 1. The occupational diseases in the dental technicians included pneumoconiosis, chronic bronchitis, asthma, pneumonia, hyposmia, allergic dermatitis, eczema, contagious dermatitis, central nervous disorder, dysfunction of finger, vertebral disorder, dysfunction of interphalangeal joint, ophthalmitis, auditory dysfunction, otitismedia, optic trauma, and bum. 2. The main related affecting factors for the occurrence of the occupational diseases in the dental technicians were elucidated as follows: On the ccurrence of chronic bronchitis, vibration of equipment and job career were affected positively. On the ccurrence of asthma, job career and career on current working part were affected positively, but exhaust ventilation, work hour were affected negatively. On the occurrence of eczema, career on current working part and vibration of equipment were affected positively, but personal protective equipment, local exhaust ventilation, isolation of gas source were affected negatively. And eczema was occurred more in methyl methacrylate work than in any other work part. On the occurrence of finger dysfunction, vibration of equipment and noise of work place were affected positively. But personal protective equipment, local exhaust ventilation, isolation of dust and gas source were affected negatively. But finger dysfunction was occurred more in metal polishing than in any other work part. On the occurrence of auditory dysfunction, noise of work place were affected negatively. The results obtained in this study can give a valuable information for a prevention of the occupational diseases in the dental technicians working in Korea, and for keeping them in healthy. This study also can be helpful for a researcher who is aiming at a identification of occupational diseases and a elucidation of related affecting factors in a similar occupation.