IntroductionOral Squamous cell Carcinoma (OSCC) is the most common oral cancer and is treated with surgery, radiotherapy and chemotherapy. Various complications of treatment include xerostomia, mucositis, and trismus, which affect patients’ quality of life. The aim of this study is to evaluate the mortality, recurrence rate and prevalence of oral complications in treated patients.Method and materialsThis cross-sectional study reviewed 326 cases of patients with OSCC who were referred to public health centers in Shiraz (Khalili Hospital and Dental School) from 2010 to 2020. All patients were contacted, and the survivors were called and examined by an oral physician. A medical record was created for them, including demographic information, location of the lesion, type of treatment, history of recurrence, metastasis and oral complications.Results53.5% of patients were male and 46.5% were female. The mean age of patients was 58.68 years. Mortality and recurrence rate was respectively 49.8% and 17.8%. The most common location of the lesion was tongue (64%). Surgery was done for all patients. 97.4% of patients complained of xerostomia, 46.2% of mucositis and 44.3% of trismus.ConclusionThe most common complications of treatment are xerostomia, mucositis, and trismus, respectively. Frequent and regular follow-ups and supportive therapies reduce these complications and improve patients’ quality of life.