Synthetic zeolites were dissolved in nitric acid, and the resulting solution used as a coprecipitant for the preconcentration of trace amounts of gallium in water samples prior to determination by electrothermal atomic absorption spectrometry (ETAAS). The gallium preconcentration conditions and the ETAAS measurement conditions were optimized. Gallium was quantitatively concentrated with the zeolites coprecipitate from pH 6.0 to 8.0. The coprecipitate was easily dissolved in nitric acid, and an aliquot of the resulting solution was introduced directly into a tungsten metal furnace. The atomic absorbance of gallium in the resulting solution was measured by ETAAS. An ashing temperature of 400degreesC and an atomizing temperature of 2600degreesC were selected. The calibration curve was linear up to 3.0 mug of gallium and passed through the origin. The detection limit (S/N greater than or equal to 3) for gallium was 0.08 mug/100 cm(3). The relative standard deviation at 1.0 mug/100 cm(3) was 3.0% (n = 5). The proposed method has been successfully applied to trace gallium analysis in environmental water samples.