Background: The present study was carried out to enable, motivate, persuade, and assist the households to use their nutritional knowledge for the promotion of their nutritional status. Methods: In this descriptive- analytical study, 188 households were randomly selected from four regions, which were selected as the population lab in Zahedan city in south-east of Iran. In the studied households, mothers were selected as the target group since they were the main caregivers in families. In the educational intervention, nutrition experts educated the participants individually. Pre- and post-tests were administered before and after the intervention. The educational program included three sessions with regard to every region of population lab. The questionnaire investigated the participants' knowledge (15 items) and practice (10 items). The total scores of knowledge and practice were calculated and participants were classified to be in weak, medium, and good status in this regard. P < 0.05 was considered as significant. Results: The mean scores of knowledge were 6.5 ± 2.7 and 8.6 ± 3.0 for before and after the intervention, respectively (P = 0.0001). A significant difference was observed between the two groups regarding the association of mothers' knowledge with their age and family size of households (P < 0.01). The results showed that the knowledge of participants was weak (55% vs. 21.5%), medium (43% vs. 51%), and good (12% vs. 27.5%) before and after the intervention, respectively. Conclusion: According to the findings, implementation of supplementary, participatory, and advisory programs are suggested for the improvement of household's nutritional practice.