Soil Transmitted Helminths (STH) infection in children are endemic in Indonesia. The four most common STH are Ascaris lumbricoides (roundworm), Trichuris trichiura (whipworm), Necator americanus and Ancylostoma duodenale (hookworms). The aim of the study was to know the influence of maternal knowledge against soil transmitted helminthes infection in children under five years

This is a quasi experimental study pre and post test design. It had been held at Posyandu in Medan on August until November 2016. Sample in this study were mothers who have children under five years old. Data collection was using structural questioners before and after intervention about STH infection. Stool laboratory test used a Kato Katz technic. Analysis data used chi square test and multiple logistic regression

The results showed that there were 23 (57.5%) children was infected by STH. There were double infection Ascaris lumbricoides and Trichiuris trichiura 16 (69.6%), Trichiuris trichiura 5 (21.7%), Ascaris lumbricoides 2 (8.7%). Mothers with good knowledge was significantly influence intensity of STH infection in children (p = 0,03; RR= 2.19).

There was influence of maternal knowledge against STH infection in children five years old. Awareness in protection of personal and environtment hygiene, periodic medical check- up should be done for improve health children

Keyword: maternal knowledge, STH infection, behaviour, hygiene