The aim of this descriptive, cross-sectional and quantitative study was to evaluate the social aspects and oral health of patients with malignant neoplasms in the head and neck (NMRCP) treated with radiotherapy (RTX) at the Ribeirão Preto Clinical Hospital (HCFMRP/USP) among 2010 to 2014, the impact on quality of life (QOL), the degree of xerostomia and salivary flow. It was analyzed medical and dental developments to verify the social and health conditions; dental examination was performed to assess the decayed, missing and filled teeth (DMFT) index, the OHIP-14 and Xerostomia Inventory questionnaire (XI) were applied for evaluating quality of life and the degree of xerostomia, and saliva stimulated was measured to quantify the salivary flow. It was analyzed 184 medical reports, 78.8% were male, mean age 57.7 years, 79.3% white, 38.0% were married, 41.8% live in town with population over 100 thousand habitants, 58.7% and 34.2% were smokers and drinkers respectively more than 30 years. The most affected sites with the primary tumor was the pharynx (31.0%) and the tongue (255%), 57.6 % of NMRCP evolved to diagnosis for a period of up to six months, 34.8% were diagnosed in 2013, 40.2% received chemotherapy treatment associated with RTX. 30.4% had hypertension, 83.2% had dental evaluation prior RTX, 48.4% did not receive dental treatment prior to RTX and 27.7% received; the alterations caused by RTX were mucositis (62.0%), dry mouth (46.2%) and candidiasis (38.0%). The survival rate varies according to the analyzed year. 40 patients participated in the dental examinations, it was found high DMFT index, on average 28.55; the quality of life was affected mainly in the food aspect and the high degree of xerostomia was associated with low salivary flow (mean 0.20 mL/min).