The primary endpoint of this study was to describe the course of sexual health outcomes prior to, during and following CRT/RT and to determine the importance of sexual function in a broader context of other oncological and functional outcomes. Eligible patients with locoregionally confined HPVOPC suitable for curative CRT/RT were approached for enrolment. Patients were assessed before treatment (baseline), week 7 of treatment (FU1), and 3- and 12-months post-treatment (FU2 and FU3, respectively). Study outcomes included sexual health (EORTC SHQ-22), quality of life (EORTC QLQ-C30), symptom burden (MDASI-HN), emotional distress (PROMIS Anxiety 7a, Depression 8b) and facial appearance and appearance distress (FACE-Q). Patient preferences were elicited using a modified version ('keeping sexual function' added) of the Chicago Priorities Scale (CPS) at baseline and FU3; items were sorted into top, middle or lower priorities; then ranked from 1-13. From October 2020 to November 2021, 100/129 eligible patients were enrolled from 3 centers: median age 61 (range 44-79), male (n = 87, 87%), partnered (n = 75, 77%), heterosexual (n = 95, 95%). Most patients received CRT (n = 97, 97%), 52% had stage I disease (n = 52). Compliance with SHQ-22 at FU3 was 89/98 alive patients. Mean sexual satisfaction scores were 52 (SD = 27, range 0-100) at baseline, 27 (SD = 20) at FU1, 40 (SD = 24) at FU2 and 48 (SD = 28) at FU3. Mixed model results indicated a clinically significant reduction in sexual satisfaction at FU1 (-25, 95% CI = -31, -20; p < 0.001) and FU2 (-12, 95% CI = -17, -7; p<0.001) from baseline, but not FU3 (-4, 95% CI = -9, 1; p = 0.15). Univariable regression analysis indicated that patient factors (cohabiting, having a sexual partner, being sexually active, non-smoker), higher global health status, other SHQ-22 items (higher importance of sex life, libido, security with satisfying their partner, erection confidence, lower fatigue affecting sex life), lower depression, as well as 'keeping sexual function' being a top priority were associated with higher sexual satisfaction at FU3. Associations with MDASI-HN symptom and interference scales, and oral toxicity measures (pain, dry mouth, taste, mouth/throat sores) were not statistically significant. For 30/87 patients, treatment affected their sexual activity quite a bit or very much. Amongst the 13 CPS priorities, 'keeping sexual function' had a median rank of 10 and 9 at baseline and FU3, respectively; 24% and 26% identified it as a top priority at these assessments. Sexual satisfaction is affected during and after CRT/RT for HPVOPC; however, on average, score differences before and 12 months after treatment are not clinically significant. Approximately one-quarter of patients consider sexual function a 'top' priority during survivorship.