KEYWORDSHypertension, Accurate blood pressure measurement, Blood pressure measurement, Blood pressure, Theory of planned behaviour 2 Abstract Patients under anthracycline chemotherapy are at risk of cardiovascular disorders, including hypertension. Error in blood pressure measurement exceeding 5mmHg may have detrimental outcomes to the patient quality of care. Studies involving nurses reveal discrepancies in knowledge and practices, which raise questions on the reliability of their BP recordings. It is not clear whether nurses taking care of these patients have sufficient knowledge and compliance regarding accurate blood pressure measurement. This study aimed at assessing knowledge, practice and associated factors regarding accurate blood pressure measurement procedures among nurses caring for cancer patients under anthracycline chemotherapy in Tanzania, guided by the Theory of Planned Behavior and Neuman's Prevention and Intervention Theory.Methods A cross-sectional study, with a quantitative approach was conducted among 181 nurses who were conveniently sampled from various hospitals in Tanzania. A structured questionnaire was used for data collection and analysis done by using statistical package for social sciences (SPSS) version 21. Descriptive statistics, Chi-square and Binary logistic regression analysis were applied.Results Based on the given 18 items to assess nurses' knowledge of accurate blood pressure measurement, the mean knowledge score was 8.6 (SD=3.6), implying poor knowledge. Those with a bachelor of Nursing and above were more knowledgeable than those with a diploma and below (AOR=2.5, 95%CI=1.281-4.914, p=0.007). Out of the maximum practice score of 40, the nurses had Mean=16 (SD=2.33) implying poor practice. Three mostly reported barriers were: Feeling unempowered, Nurses' workload, and unconducive working environment. The results conform to the theory of planned behavior and Neuman's Prevention and Intervention Theory. Conclusion Nurses caring for patients in anthracycline chemotherapy in Tanzania have poor knowledge and poor practice regarding accurate blood pressure measurement.Institutional programs to educate nurses about accurate blood pressure measurement may have an impact on attitude and intention to practice accurate blood pressure measurement.Considering the barriers to accurate blood pressure measurement, and the impact of unstable blood