Abstract Background Oral diseases and associated illnesses interfere with cancer treatment, increase morbidity, prolong hospital stay, and increase costs. Oral care of children with cancer is essential to prevent oral diseases and decrease its symptoms. Standardized oral health and hygiene (OHH) practices must be a priority and incorporated as a routine cancer care quality. To improve OHH, baseline information of practices, processes and institutional support are necessary. Here, we report the steps we followed to develop a tool for evaluating OHH practices, support, and resources available in a pediatric cancer unit. Methods We conformed a working group (WG) integrated by healthcare professionals in pediatric, infectious diseases, oncology, and dentistry acquainted with the care of children with cancer. The steps proposed by the WG included: (1) literature review of published surveys in OHH; (2) interviews with practicing healthcare providers regarding OHH in pediatrics; (3) identification, adoption and adaptation of the Hand Hygiene Self-assessment framework (HHSAF), a survey model based on the multimodal improvement strategy (MMIS); (4) building of OHH tool; (5) validation test of OHH tool; and (6) pilot testing in recruited pediatric hematology and oncology centers. Google form version 0.8. Microsoft office excel 2021 (18.0) was used to build the OHH survey and obtain the WG member responses. The final draft of the survey was approved by WG members. We will evaluate survey validity in the pilot test among members of the PRINCIPAL network, a community of pediatric infectious disease experts and preventionists of Latin America. Results We found few reports on OHH practices in children cancer surveys. The WG met virtually and monthly from March to December 2023 to build the OHH survey. Our final survey version was organized following the model of the HHSAF and integrated into five main sections. These sections had items (Q) that requested answers regarding OHH practices and resources and institutional support (6Q); training and education of patients, families, and healthcare providers (6Q); evaluation and feedback of OHH processes in pediatric oncology unit and OHH practices of patients (6Q); reminders of OHH practices in the workplace (3Q); and hospital leadership support (2Q). The survey was made up of multiple choice and Likert scale questions. Each of the answers had a weight, and if all the items were present, the total was 400 points. Based on the total points obtained, we categorized the quality of the OHH practices of the pediatric oncology unit in inadequate (0-100); basic (101-200), intermediate (201-300), advanced (>300). The survey tool must be answered by an assigned team of the pediatric oncology unit oral health including a family member representative, and it could take less than 15 minutes to complete. Conclusion We developed a 21-item OHH practices survey following the WHO recommendations to use a MMIS model. We found that our newly developed tool was comprehensive and potentially helpful to assess OHH practices and identify success factors in best practices in OHH in pediatric oncology units. Our next step is pilot testing to evaluate our survey tool validity and reliability.