The burden of oral health diseases in children with leukaemia and the impact of cancer treatment on their oral health have not been studied in Sudan. The present study assesses the oral health status of leukemic children through measuring caries experience, gingival status, oral hygiene status and mucositis. It also explores the association between the oral health status of children with leukaemia and their parental education, oral hygiene habits, treatment stage and type of leukaemia. A cross sectional hospital-based study was conducted at the Radiation and Isotope Center Khartoum, Khartoum State. A total of 87 children were included in this study. Data were collected by interviewer questionnaire and clinical examination. The oral health status revealed high prevalence of untreated dental caries (37.9%) and the majority (67.9%) of children had poor oral hygiene. Nearly, all children with leukaemia (93.1%) had never visited a dental health facility in their lives. Regarding the treatment stages of leukaemia, the severity of dental caries was found to be more significant in the maintenance phase, while oral mucositis was more significant in the induction phase.