This descriptive study was undertaken to measure quality of life score and investigate the correlation between the demographic characteristics, the diagnostic related characteristics, physical symptom and quality of life of breast cancer patients undergoing radiation therapy as on attempt to provide basic data to help them attain better qualify of life. The subjects for this study were 74 out-patients undergoing radiation therapy at C University hospital in Gwangju, from June, 1998 to July, 2000. The data were obtained using a convenient sampling technique. The tool of this study was the quality of life scale developed by Ro Yoo Ja. The data were analyzed using the SAS program for percentage, mean, standard deviation, Pearson Correlation Coefficient, GLM. The results were as follows: 1. The total average score for quality of life of the subjects was 137.22 and the range was from 38 to 227, item mean score(range 1-5) was 3.15. For each factor in qualify of life of life score, the mean scores(range 1-5) were as follows; family relationship 3.69, relationship with neighbors factor 3.40, self esteem 3.10, physical state and function 2.95, economic life 2.91, emotional fate 2.88. 2. The incidence of physical symptoms was seen fatigue($82.4\%$), skin change($43.2\%$), alopecia($41.9\%$), pain($41.9\%$), anorexia($39.2\%$), anemia($39.2\%$), and headache($31.1\%$) in that order. 3. The result of the analysis of the relationships between the quality of life scores and demogaphic characteristics were as follows : there were significant differences, between age(F=3.44, p=0.013), educational level(F=3.84, p=0.007), duration of marriage((F=5.06, p=0.003) and monthly income(F=4.72, p=0.005). 4. The result of the analysis of the relationships between quality of life scores and diagnostic related characteristics was as follows: there was a significant difference between incidence durations(F=5.02, p=0.003). 5. The correlation of emotional state, economic life, self esteem, physical sate & function, relationship with neighbors, relationship with family in quality of life of cancer patients revealed a positive correlation.