Introduction Maxillomandibular reconstruction has various functional, aesthetic, and psychosocial effects that can decrease patients' health-related quality of life (HRQOL). The aim of this study was to compare HRQOL outcomes in older and younger patients undergoing maxillomandibular reconstruction. Methods A cross-sectional study of patients undergoing maxillomandibular reconstruction surgery between November 2008 and January 2021 was conducted. Participants completed the FACE-Q Head and Neck Cancer Module, M.D. Anderson Dysphagia Inventory (MDADI), and Speech Handicap Index (SHI). Results from these instruments were used to compare HRQOL outcomes in old (≥70 years) and young (<70 years) patients. Results Ninety-nine patients who underwent maxillomandibular reconstruction completed the instruments, of which 33% were aged ≥70 years. Older age was associated with improved FACE-Q speaking (P = 0.045), FACE-Q cancer worry (P = 0.050), and SHI score (P = 0.013). After adjusting for the effect of radiotherapy, age was associated with improved FACE-Q speaking (P = 0.012), FACE-Q smiling distress (P = 0.040), FACE-Q worry (P = 0.032), and SHI scores (P = 0.004). Older age was associated with an increased likelihood of postoperative complications (P = 0.02) and medical complications (P = 0.012). Conclusion In patients undergoing maxillomandibular reconstruction, older age (≥70 years) was associated with better HRQOL outcomes in domains relating to speech and cancer worry. In all other HRQOL outcomes, the two age groups performed similarly. Given these results, it is perhaps the responsibility of surgeons to reduce the emphasis of age when assessing a patient’s eligibility for maxillomandibular reconstructive surgery.