To examine the association between home safety hazards and unintentional poisoning in children in Mongolia. We conducted a case-control study using structured questionnaires to investigate safety behaviours, safety equipment use, and home hazards in households with or without children aged 0-5 years who had suffered from poisoning at home (i.e., cases and controls). We recruited 190 cases (105 medicinal and 84 non-medicinal poisonings, and one each) at the National Center for Maternal and Child Health and 379 controls in the communities between 1 March and 30 October 2021. There were large differences between cases' and controls' households in safety behaviours and home hazards: the failure to store all medicines out of reach of children (68% of cases vs. 25% of controls), the failure to store all medicines safely (out of reach, locked or non-existent) (61% vs. 22%), the failure to put all medicines away immediately after use (77% vs. 43%), the presence of things that a child could climb on to reach high surfaces (82% vs. 67%), the presence of medicines transferred into different containers (28% vs. 9%) and the presence of household products transferred into different containers (28% vs. 16%). These home safety hazards were strongly associated with poisoning after controlling for confounders. Children's risk of unintentional poisoning was strongly associated with the unsafe storage of potentially poisonous agents by caregivers and home hazards. Since unsafe storage is widespread, a fail-safe approach such as child-resistant closure of medicines and household products should be considered.