Abstract: ObjectiveTo optimize the instrumentation condition and matrix modifiers of graphite furnace atomic absorption spectrometry(GFAAS)to determine trace barium in drinking water.MethodsThe drinking water samples were mixed and filtered,with calcium nitrate(CaNO₃₂)as the matrix modifier;then the content of barium in the samples was analyzed with optimized GFAAS.ResultsThe lowest detection limit of the method was 3.1×10^-12 g;the recovery of standard addition was 94.0% -98.0% ;the relative standard deviation(RSD)was less than 7.6% ;and the linear range was 0-50 μg/L,with a correlation coefficient of 0.9996.ConclusionThis method is sensitive,accurate for determination of trace barium in drinking water.