Malnutrition can be caused by inadequate food, disease or disability. Two factors cause malnutrition, namely direct causes and indirect causes. The direct causes are the lack of quantity and quality of food consumed and the suffering from infectious diseases. Indirect causes are household food availability, behaviour, and health services. This research is a quasi-experimental research design with a control group pretest-posttest. The study was conducted in the Seberang Padang Health Center area, Padang City, West Sumatra. This study used a quasi-experimental approach with a control group before pre-and post-test. The sample size of 140 proved sufficient for the study data to be collected using a structured questionnaire at pre-test and six months post-intervention. Data were analyzed using the chi-square test. The prevalence of children with infectious diseases decreased severely at the post-test was 37.2% (72.9% to 35.7%) in intervention and increased by 11.4 % (42.9% to 54.3%) in the control group. There was a statistically significant change in the prevalence of infectious diseases between the intervention and control groups during the pre-test and post-test (p=0.001 and p=0.041). The six-month integrated nutrition health intervention model could reduce the incidence of infectious diseases in malnourished children. There are several suggestions that the author conveys to the Padang City Health Office to conduct regular training for health workers on the concept of providing nutritional care to various age groups of toddlers and provide an effective and efficient form of documentation of nutritional status assessment in controlling the outbreak of infectious diseases in toddlers.