Among the 292 patients with nonmetastatic oropharyngeal cancer of which 272 [93%] were HPV–positive tumors, 58 patients (20%) were treated with IMPT and 234 (80%) with IMRT. With a median follow-up of 26 months, this study reported no significant differences in 3-year OS (97% IMPT vs 91% IMRT; P = .18), PFS (82% IMPT vs 85% IMRT; P = .62), or LRR (5% IMPT vs 4% IMRT; P = .59); however, the incidence of acute toxicities and chronic xerostomia of grade ≥2 was significantly higher for IMRT compared with IMPT.