Objective: To evaluate cost of illness of locally advanced cervical cancer patients from societal perspective in three scenarios including completely cured without severe late side effects (S1), completely cured with late grade 3-4 gastrointestinal side effects (S2.1) or genitourinary side effects (S2.2), and disease recurrence and death (S3). Methods:  The incidence-based approach was conducted. The cost was calculated for 5-year time horizon starting for the treatment initiation. Direct medical costs were extracted from hospital database. Cost of using two-dimensional technique and three-dimensional conformal radiation therapy were calculated separately. Direct non-medical costs and indirect costs in terms of productivity loss were based on actual expenses from the interview of 194 locally advanced cervical cancer patients from two tertiary hospitals in Bangkok, during June to December 2019. All costs were converted to US dollar in 2019 values. Results: For 5 years, cost of illness per patient for using two-dimensional technique and three-dimensional conformal radiation therapy were US $8,391 and US $10,418 for S1, US $18,018 and US $20,045 for S2.1, US $17,908 and US $19,936 for S2.2, and US $61,076 and US $63,103 for S3, respectively. The economic burden for newly diagnosed locally advanced cervical cancer patients in Thailand in 2018 was approximately US $129 million and US $131 million for using two-dimensional technique and three-dimensional conformal radiation therapy, respectively. Cost from S3 accounted for 70% of all total cost. Premature death was the most important cost driver of cost of illness accounted for 64 % of the total cost estimates. Conclusions: Cost of illness of locally advanced cervical cancer patients produced significant economic burden from societal perspective. Disease recurrence and early death from cancer was the most influential cause of this burden.