Self-management actively involves individuals in the diseases process, making them responsible in managing the symptoms of diseases. Pre and post-test were conducted among 30 breast cancer patients in two tertiary hospitals in southeastern Nigeria. Validated self-management scale was used as instrument for data collection. Data was collected in three stages. Educational intervention was developed and implemented to improve self-management among the respondents. Outcome assessment was conducted twice in the course of the study: at pre-test and post-test. Data collected was analyzed using descriptive statistics: frequencies (%). Convergent correlation was determined using Pearson correlation. Significant differences between the pre-and post-test were compared using McNemar’s test. Impact of demographics on self-management was determined using regression analysis. All significant values accepted at P<0.05. Result showed that 16(53.33%) of the patients were more than 50 years, 13(43.33%) had been living with breast cancer for less than one year, while 16(53.33%) had their left breast affected. Also 9(30%) of the respondents had no children, 22(73.33%) breast fed their children, 18(60%) were in their menopause while 27(90%) had no history of breast cancer in their family. The composite scores of 0.46 and 0.53 at the pre and post-test study showed difference in the level of self-management among the respondents. P-value of 0.000015 showed a statistically significant difference in the level of self-management among the breast cancer patients in the pre and post-test study. Self-management in the breast cancer patients was determined using the validated self-management scale. Educational intervention resulted in improved self- management among the breast cancer patients. Use of self-management scale will improve self-management and quality of life of breast cancer patients.