This work aimed at evaluating patients' swallowing functions by a newly validated swallow-specific questionnaire, the Sydney Swallow Questionnaire (SSQ), in a cohort of oral and oropharyngeal cancer patients. Mean/median SSQ scores were calculated and compared with study variables using the Mann-Whitney U test and Kruskal-Wallis test. The mean composite SSQ scores (SD) for the base of tongue, oral tongue, and tonsillar cancer patients were 663.8 (382.8), 456.2 (407.6), and 283.0 (243.1), respectively (p = 0.005); for advanced vs. early T stage disease they were 918.1 (319.5) vs. 344.8 (292.1) (p ≤ 0.001); for patients <60 years vs. ≥60 years they were 549.3 (415.1) vs. 314.0 (247.3) (p = 0.02); and for patients with reconstruction vs. without reconstruction they were 676.5 (410.5) vs. 331.9 (286.5) (p = 0.002). SSQ is a useful tool for evaluation of swallowing in head and neck cancer patients. Site of cancer, T stage, patient's age, and reconstruction directly affect post-treatment swallow outcome.