I n toddlerhood, children begin to understand the concept of autonomy so that behavior appears to be able to choose things they like, one of which is the behavior of choosing food, namely picky eaters. If the nutritional intake is less varied, there is a possibility that the child will not get sufficient macro and micro nutrition to support his development. In addition to nutritional intake, responsive parenting is essential in meeting children's needs, such as adequate sleep time. Sleep in children facilitates the maturation and repair of body cell functions, including brain cells and hormones that play a role in development.METHODSThis study used a cross-sectional study design using primary data from 138 respondents who were toddlers in the Posyandu of Tanjung Duren Utara Village. Assessment of picky eater behavior using the Children’s Eating Behavior Questionnaire (CEBQ), sleep duration using the average questionnaire of sleep duration and child development using the Indonesian pre-screening developmental questionnaire, Kuesioner Pra-Skrining Perkembangan (KPSP). Analysis of bivariate data using the Chi-square test with a significance level of p<0.05.RESULTSAmong the 138 respondents, it was found that the majority had picky eater behavior, namely 93 (67.4%) children. There were 101 children (73.2%) with adequate sleep duration. The proportion of appropriate child development is 79 children (57.2%). The relationship between picky eater behavior and development through statistical tests obtained a p = 0.035 (p <0.05). Sleep duration and development p=0.298 (p>0.05).CONCLUSIONSThere is a relationship between picky eater behavior and development in under-fives. There is no relationship between sleep duration and results in development under-fives.