Aims: Very little works have been reported on the issues of burden perceived by the caregivers of head-and-neck cancer (HNC) patients. Job of the caregiver is complex, and it limits their social, psychological, and economical well-being. Our study aims at assessing caregivers' strain during radiation therapy (RT) of HNC patients using the Modified Caregivers' Strain Index (MCSI) Scale. Materials and Methods: In this single-institutional cross-sectional study, we interviewed caregivers of HNC patients undergoing curative RT. Along with MCSI, a 13-point questionnaire, which was self-administered in local languages; we collected baseline data of patients and their caregivers. Scores were evaluated. For each question, score varies 0–2. Higher the Median Hazard Score (H Score), more was the level of the strain. Results: We interviewed 24 participants. Response rate was 100%. About 45.8% of patients were in Stage III. The median age of caregivers was 40 years; 58.3% were male, 79.2% were employed, and 58.3% were belonging to the upper-lower class. Nearly 66.6% were spouse of the patients and 70.8% belong to joint family. In MCSI score analysis, H Score was 22 (range 14) with a minimum score of 14 and maximum score of 26. The most common score was 20. About 65.1% of participants responded Score 2 in all aspects of strain indices. Travel time had a significant positive association with total H Scores (Pearson's r = 0.663, P < 0.05). Conclusion: Majority of the caregivers was suffering from severe physical, personal, emotional, and social/financial strain. This issue must be addressed in holistic cancer care.