Introduction: can cause significant tissue damage; alter limb function, pain and decreasing quality of life. Nurses play a significant role in the prevention, identification and follow-up of the complications. Objectives: This study was conducted to evaluate the oncology nurses' knowledge about chemotherapy related - extravasation injuries, risk factors, preventive measures, and management practices. Methods: A descriptive cross-sectional design with a convenience sample was used. A sample of 110 oncology nurses completed the knowledge test. European Society for Medical Oncology (ESMO) - European Oncology Nursing Society (EONS) management of chemotherapy extravasation Clinical practice guidelines were used to develop the knowledge test. Results: The oncology nurses' knowledge of chemotherapy related-extravasation's definition and signs and symptoms was satisfactory. However, knowledge about risk factors was limited. Generally, the results showed that high percentage of the participants had correct information regarding the procedure domain. However, knowledge deficit regarding site of insertion, and cannula characteristics were reported. The results showed that there was knowledge deficit among the participants regarding all specific treatment practices. Conclusions: The current study provides a baseline data about oncology nurses knowledge and practice regarding chemotherapy related-extravasation care. Continues education, seminars, and workshops should be conducted for oncology nurses to increase their knowledge and strengthen their competencies.