Caesalpinia sappan L. is a medicinal plant generally used to promote blood circulation and as an anti-thirst remedy. Fifteen samples were collected from different locations in Thailand. The aim was to identify parameters including the anatomical and histological characters as well as the thin layer chromatography (TLC) fingerprint. The quality parameter results of total ash, acid insoluble ash, ethanol and water soluble extractive values, loss on drying, and water content were 0.87±0.14, 0.44±0.14, 2.94±0.57, 3.77±0.64, 8.50±0.37, and 8.52±0.43% by weight, respectively. TLC-densitometry and TLC-image analysis were performed to detect brazilin using silica gel 60 GF254 as the stationary phase and chloroform, ethyl acetate, and formic acid (10:8:2) as the mobile phase. The results of brazilin from the TLC-densitometry and TLC-image analysis were 1.259±0.285 g/100 g and 1.256±0.266 g/100 g of dried heartwood, respectively. The result showed that both techniques were not statistically significantly different.