Problem statement of the study is to effectiveness of structured teaching programme on breast self examination among adult women at selected community area in Chennai.The objective of this study was To assess the knowledge regarding breast self examination, before and after structured teaching programme among adult women. To determine the effectiveness of structured teaching programme on knowledge regarding breast self examination adult women.To find out the association between knowledge score among women & with their selected demographic variables age, religion, education, type of family and marital status.The methodology of the present study was conducted at selected community area chemmencherry at chennai. The sample for this study consisted of 100 adult women in selected community area. Stratified random sampling technique was used for the sample selection. The tools used for the data collection was self administered Multiple choice questionnaire which consist of two parts, part one was demographic data and part two was knowledge of breast self examination questionnaire. Descriptive statistics (frequency, percentage, mean, and standard Deviation) and inferential statistics (Chi square, paired „t‟ test) were used to analyze the data and to test the hypotheses.The following were the results of this study: As per demographic characteristic, majority of women 43 (43%) were between age group of 20-30years,47 of them (47%) were Hindu religion,34 of them (34%) were no formal education, 60 of them (60%) were nuclear family members, 81 of them (81%) were married women. The frequency and percentage of pretest and post test level of knowledge regarding breast self examination shows Majority of female students in pretest 95 of them (95%) had inadequate knowledge, remaining 5 of them (5%) had moderate knowledge and none of them had adequate knowledge regarding Breast self examination but in post test majority 77 of them (77%) had adequate knowledge,remaining 23 of them (23%) of them had moderately adequate knowledge and none of them inadequate knowledge regarding Breast self examination. Over all comparison of mean values between pre test 8.35 and post test 24.18 of knowledge regarding breast self examination and „t‟ value 3.99 obtained was found to be significant at 0.05 level. This was conducted through structured teaching programme is effective in improving awareness regarding breast self examination.