Abstract: The polarographic adsorptive wave of Hg ( Ⅱ )-palladium reagent (3-hydroxy-1-p-sul-fonatophenyl-3-phenyltriazene) complex in 0. 05 mol/L Na₂B₄O₇ medium was studied for the first time and a sensitive SSP(single sweep polarography) method for the determination of trace of Hg( Ⅱ ) has been developed. The complex, corresponding to Hg(R)₂ with logβ'=8. 30, is strongly, adsorbed on the surface of the mercury electrode. The polarographic wave is attributed to the reduction of Hg ( Ⅱ ) In the complex to Hg. The linear range is from 7×10^-8 to 1×10^-5 mol/Land the detection limit is 4 × 10^-8 mol/L. The method has been used to determine Hg(Ⅱ ) in water and biological samples.

Key words: Adsorptive wave, Determination of mercury, Palladium reagent