A pre-experimental research to assess the effectiveness of structure teaching module regarding knowledge on common respiratory disorders and its prevention identified the overall mean knowledge score of mothers of under five children during pre-test was 9.99 ± 5.52 (SD) which is 35.73% of the total mean score, whereas in post-test, the mean score was 22.23 ± 4.55 (SD) which is 76.17% of the total mean score revealing gain of 40.43% in knowledge score. Area wise assessments shows that during post-test mean score was above 67.2% of the total score in all areas, which reveals that mothers of under five children had gained adequate knowledge. It is observed that during pre-test the mothers of under five children had poor overall knowledge whereas it was good after the implementation of structured teaching module. Highly significant difference was found between pre-test and post-test knowledge score (P<0.05) and no association was found between post test knowledge scores of mothers of under five children when compared with selected demographic variables. Keywords: Under five children; Common respiratory disorder; Knowledge.