Background Patients after completing their treatment for HNC, are often functionally challenged by the acute and chronic complications in the oral cavity such as oral pain, limited mouth opening, xerostomia etc. These complications are known to reduce their OHRQoL, because of restricted food intake, limited social activity and economic growth, therefore impacting their overall well-being and survival. This study aims to assess the OHRQoL and its associated sociodemographic factors, oral hygiene related factors and oral clinical parameters such as OH status and OM grade in HNC survivors within one-year post cancer treatment.Methodology This was a cross-sectional study performed among HNC survivors at the ENT and dental clinics of Aga Khan University Hospital, Karachi. OHRQoL was assessed using EORTC QLQ H&N – 35, patients were examined for oral hygiene status using OHI- simplified and oral mucositis grade using WHO oral mucositis scale at one point in time. One sample t- test and multiple linear regression was used to test OHRQoL and its associations with the sociodemographic and clinical factors.Results The results of the study showed an overall higher mean score for OHRQoL of 25.02 ± 15.86 (95% CI 21.46–28.57), with difficulty in mouth opening and dry mouth because of salivary dysfunction among the most affected domains with higher symptoms scores in the study population. Significant association of OHRQoL were found with BMI, OH status, marital status, monthly income, gender and fluoride toothpaste use in HNC patients within one-year post cancer treatment (p < 0.05).Conclusion: High mean score for OHRQoL in HNC patients suggests their QoL is negatively impacted by their poor oral health post cancer treatment, therefore it is important to evaluate and modify the current treatment modalities and involve multidisciplinary teams, to improve their OHRQoL thereby enhancing overall QoL.