This study aimed to identify the level of health literacy and factors related to inadequate and problematic levels health literacy among elderly in Thailand. This cross-sectional analytical study used the data set from the National Health Literacy Survey of Thailand. The study population of this study was Thai citizen aged 60 years and older residing in all 13 zones which consisted of 77 provinces of 4 regions in Thailand. A total of 6,477 elderly who passed the inclusion and exclusion criteria were recruited. Multivariable analysis was performed by including all independent variables into the model by assigning significant p-value. Our study observed that 37.58% of elderly had problematic health literacy level (51-66 %) with 95% CI: 36.40-38.76. Our multivariate analysis revealed that factors associated with problematic and inadequate level of health literacy were elderly having age group of ≥ 80 years (Adj.OR 2.12 ,95% CI:1.64-2.740, p-value <0.001), elderly without formal education (Adj.OR=6.08, 95% CI: 3.80-9.73, p-value <0.001), those who can't read and write fluently with Adj.OR 1.49 (95% CI, 1.15-1.94, p-value 0.003), (Adj.OR 1.53, 95% CI, 1.18-1.98, pvalue 0.001) respectively. Furthermore, respondents who were never had health information acquisition from physician (Adj.OR=1.52, 95% CI, 1.32-1.74, with p-value <0.001), health professionals (Adj.OR=1.35, 95% CI, 1.17-1.56, p-value <0.001), health volunteers workers (Adj.OR=1.75, 95% CI, 1.50-2.03, p-value <0.001) and not using glasses or contact lens to see (Adj.OR=1.15, 95% CI, 1.01-1.32, p-value 0.035) were significantly associated with inadequate as well as problematic level of health literacy respectively. Nearly a quarter of the elderly has adequate level of health literacy. Moreover, the raising age amongst the elderly was significantly associated with inadequate health literacy level.