ABSTRACT: Children with cancer commonly present oral health impairments due to lack of orientation about oral hygiene, which should be directed to caregivers since they are essential in this process. We developed and validated a guideline directed to caregivers for oral hygiene of children with cancer. This exploratory methodological study developed an educational guideline in three stages: analysis of oral health of children attended at the oncology service; literature review and development of the guideline for oral hygiene; semantic, appearance, and content validation by dentists, education professionals, and the target population. We used the Educational Content Validation Instrument in Health, and agreements of ≥ 80 % among evaluators were considered to maintain or modify the assessed items. Professionals and caregivers were mostly female; the latter were predominantly mothers with low educational level from inland areas of Pernambuco state (Brazil). Most professionals had more than ten years of experience in pediatric dentistry. Agreement was > 80 % in all items. The content of the guideline for oral hygiene was valid and relevant to be used in children with cancer.