Purpose: The use of port catheters is well accepted in the management of patients with malignancy. In this study, we compare the technical success and the complication rates of ultrasound guided Port-A-Cath implantation with doing this procedure by using the anatomical landmark method. Methods: In a retrospective study, from 2006 to 2009, medical files of 104 patients who had undergone Port-A-Cath implantation were reviewed. The indication for port catheter implantation was malignancy in all cases. Among our patients, Port-A-Cath implantation was done in 63 patients by using landmark method and in 41 patients by guidance of ultrasound. All patients had been observed for complications including pain, port infection, and port thrombus, thrombus of central veins, skin necrosis, and success in using of Port-A-Cath for at least one month following the procedure, in the vascular clinic. Results: in landmark method group, 2 catheters were non-functional just after placement (3.2%) while all Port-A-Caths in ultrasound-guided group were functional. Ten patients (15.9%) in land mark group and 1 patient (2.4%) in ultrasound-guided group were complicated. The difference between complication rate in anatomic landmarks method and ultrasound-guided method was statistically significant (p < 0.04). There was no significant difference in two groups in duration of port placement (p < 0.345), age (p < 0.444), site of port placement (p < 0.244) or type of malignancy (p < 0.18). Conclusion: Considering high rate of success and low complications in placement of Port-A-Cath with ultrasound guidance, this method is superior to the land mark method in patients with malignancy.