Growth monitoring in toddlers requires standardization by looking at the scope of weighing (D / S) or the number of toddlers weighed compared to the total number of toddlers in a health center work area at a period of time. The study aimed to determine factors that affect the activeness of visiting Posyandu. The research method was a survey with a cross-sectional study design. The population was all toddlers registered in the Hulonthalangi Health Center working area including 998 toddlers, while sampling was carried out by simple random sampling with 91 respondents. The variables included the activeness of Posyandu visits, the age of the mother, the mother's education, the mother's occupation, and knowledge of mothers under five. The results of the study showed that many of the toddlers mothers had age 20-35 years (63.7%), maternal education ≥ 9 years (64.8%) and working mothers (18.7%), boys toddlers (54.9%). Bivariate analysis showed there were not association between mothers age (p value = 0.550), mothers education (p value = 0.727), mothers occupation (p value = 0.669) dan toddlers sex (p value = 0.094) with Posyandu visit. There were association between mothers knowledge with Posyandu visit (p value = 0.018), toddlers age 1 – 2 years (59.3%) have association with Posyandu visits (p value = 0.015). The conclusion showed association between knowledge of mothers and toddlers age with activeness of visiting Posyandu.