Background: Acute Respiratory Infection (ARI) is one of major causes of toddlers mortality in the world and it is recognized as a health problem that often occurs in toddlers in developing countries. The prevalence of ARI in Indonesia reached 25% in 2013. In Papua, ARI occupies first rank of 10 major health problems. ARI is strongly influenced by environment and host factors. This study aims to determine the rule of sosio-determinant factors towards toddlers’ ARI incident in district of Arso-Keerom, Papua. Methods: This study was an observational analytic with cross sectional approach. The total of sample was 100, collected based on propotional stratified random sampling in district of Arso-Keerom, Papua. Instruments used in this study was a questionairre and measurement. Result: The incidence of ARI in toddlers was 72% and 28% toddlers without ARI. Bivariate analysis showed an association among ventilation (p=0,012), dwelling density (p=0,034), cleanliness of floor (p=0,029), cigarette smoke (p=0,035), nutritional status (p=0,043), and immunization status (p=0,027) with toddlers’ ARI incident. In other hand, there was no correlation among temperature (p=1,000), natural lighting (p=0,721), fuel cook (p=1,000), mosquito insecticide (p=0,824), vitamin A status (p=0,715), and mother’s behaviour to treat children (p=0,318) with toddlers’ ARI incident. Conclusion: Sosio-determinant factors significantly associated with toddlers’ ARI in Arso district are ventilation, dwelling density, cleanliness of floor, cigarette smoke, nutritional status, and immunization status. The cooperation among community (family), department of health, and goverment are needed in effort to overcome ARI’s problem. |