T The government efforts to reduce the prevalence of DBD in Indonesia one of them is by 3M Plus program. The 3M Plus program is an effort to prevent the spreading of DBD disease, starting from the eradication of Aedes aegypti mosquito larvae involve methods through physical ,biological and chemical. Since high amount of DBD’s incidents in Indonesia, encourage the scientist to evaluate further about Correlation between knowledge and behavior toward 3M Plus. The design of this research is analytical observational with cross sectional study approach is, and the election of Sample is using non-random purposive sampling methods with univariate and bivariate analysis. This research was conducted from November until December 2015 in Kelurahan Mangga Dua Selatan. The subjects involved are 246 respondents. The data were collected by questionnaires. The results showed that 34.1% has less knowledge about dengue fever. While the other 65.9% has more knowledge. Concerning the attitude about prevention of dengue fever , the positive attitude has value greater frequency of 58.1% than the negative behavior which is 41.9%. Besides, concerning about the act of preventing the dengue fever with less act is 17.5% and with more act is 82.5%. This research found there is no significant correlation between knowledge and action obtained from probability value of p=0.126 and there is no significant correlation between behavior and act obtained from probability value of p=0.089. It was concluded that there is no correlation between knowledge and act of 3M Plus and no correlation between behavior and act of 3M Plus. This is likely due because of low level education factor that the mothers has and the lack of facilities and infrastructure to do the act of 3M Plus.