In this paper the evaluation of validation characteristics and quality control of the CUPRAC method was carried out and using the tested procedure total antioxidant capacity of aqueous and methanol extracts of Yunnan Baiyao powder was determined. The CUPRAC method is based on the absorbance measurement of the CUPRAC chromophore, Cu(I)-neocuproine (Nc) chelate, formed as a result of the redox reaction of antioxidants with the CUPRAC reagent, bis(neocuproine)copper(II) cation [Cu(II)-Nc] at 450 nm. Evaluation and quality control of the CUPRAC method was carried out using a comprehensive prevalidation strategy according to Grdinić and Vuković (2004). The prevalidation procedure included characterization of the groups from 1 to 6, checking of limiting groups, homogenity testing, the quality of analyte-signal relationship, outlier recognition, and evaluation of limiting values. Performance characteristics showed an ideal linear calibration function ( Sˆ = 0,002 x), an ideal analytical evaluation function ( xˆ = 525,6 S), a very low limit of detection (LD= 16,03 μM), a somewhat poorer limit of quantitation (LQ=97,46 μM) and a lower precision ( rx s ˆ 1,54- 30,69%) and accuracy (Δx 1,74-16,21 %). The carried out prevalidation also indicated disadvantages of the procedures such as inhomogeneity of blank values, which influences the total quality of procedure. The total antioxidant capacity of aqueous and methanol extracts of Yunnan Baiyao powder is expressed as μg TE/g powder. It has been determined that the aqueous extract of Yunnan Baiyao powder has a higher antioxidant capacity ( 897,2 ± 51,5) than the methanol extract (702,3 ± 68,0).