Quantitative approach was used with pre-experimental one group pre-test & post-test design. The Planned teaching program regarding prevention and management of diarrhoea among mother of toddlers. The study was conducted at Ugat, Canal road, Surat, Gujarat. The samples of 60 mothers were selected through Non probability purposive sampling technique. A structured knowledge questionnaire was prepared to assess the knowledge of samples. Content validity of the developed tools and Planned teaching program was established by 6 experts and necessary modification were made as suggested by them. Reliability of the tool was ascertained by Karl Pearson's coefficient correlation (r) method. The mean pre-test knowledge score was 11.9 and mean post-test knowledge score was 21.63. Significance of the difference between pre-test and post-test knowledge was statistically tested using paired 't' test and it was found significantat 0.05 level (t-92.56, t2.00 respectively). There was significant increase in the knowledge of the samples after administration of the Planned teaching programre garding prevention and management of diarrhoea among mother of toddlers. Hence it is concluded that Planned teaching program was effective in improving the knowledge of the mother of toddlers.