Aim: The aim of this study was to determine the knowledge levels of Turkish nurses regarding implantable port catheter care. Methods: A descriptive method was used inside a university hospital that was located in a Turkish metropolis. The data were collected via a questionnaire that was given to a total of 45 nurses who were employed in the internal medicine clinics where the oncology patients were treated. Results: In this study, 42.2% of the nurses received in-service training about the implantable port catheter. It was determined that the mean knowledge point was 15.13 +/- 4.78. The difference between the knowledge points of the nurses regarding implantable port catheter care, based on whether or not the nurses had received in-service training, was statistically significant. Moreover, it was determined that the majority of the nurses did not know where the implantable port catheter is placed, its period of use following implantation, the amount of normal saline to be used for washing the catheter, the special port (Huber) needle, the number of the needle, and the exchange time of these needles. Conclusion: In this study, there existed significant differences between the scores of the nurses who received in-service training about the implantable port catheter and the scores of those who did not receive in-service training. The majority of the nurses who participated in the study were willing to receive in-service training regarding this subject. Thus, the organization of in-service training programs and the implementation of care, according to the developed standards and guidelines, are considered as significant for reducing the occurrence of the complications that are related to the use of the implantable port catheter.