Perforation of maxillary sinus is a common complication of implant placement in posterior maxilla. The purpose of this study was to evaluate the prognosis of sinus perforated implants placed in partially edentulous maxillae. Eighteen sinus perforated implants in 15 patients were examined for cumulative survival rate, radiographic preoperative bone level, and radiographic marginal bone level change. Twenty-two non-perforated implants in the same patients served as control. The results were as follows; 1. There was no statistically significant difference in cumulative survival rate between sinus perforated implants and non-perforated implants (P>0.05). 2. There was no statistically significant difference in the marginal bone level between sinus perforated implants and non-perforated implants (P>0.05). 3. There was no statistically significant difference in cumulative survival rate according to the preoperative bone level (P>0.05). These results suggests that perforation of maxillary sinus may not affect implant success in posterior maxillae.