A study was carried out to investigate the technical factors and the patient dose (entrance and absorbed dose) in chest P-A radiography based on the 86 hospitals in Seoul from July 1 to July 30, 1989. As a result of this study, main finding were as follow : 1. 51.2% of the surveyed hospitals made use of $60{sim}69;kVp$ as tube voltage in chest radiography 2. The majority of the surveyed(88.3%) have the use of $6{sim}20;mAs$ as tube current-time. 3. Percentage absorbed doses in patient were showed more than 90 percent in every tube voltage. 4. Object densities were all much the same in all tube voltages. 5. 48.8% of surveyed entrance doses ranged from $100;{mu}Sv$ to $190;{mu}Sv$, and the mean dose was $158;{mu}Sv$.