A flow injection suction elution method on-line sorption and preconcentration system coupled to flame atomic absorption spectrometry(FAAS) was developed for the determination of trace Ni in water.During the elution procedure,the eluent was pumped into KR by the suction force.Thus,the dispersion of the analyte was decreased notably,and absorbance peak value and enrichment factor(EF) value were improved.Emptying step was added in order to insure the veracity and repeatability of the experiment.With 60 s(sample throughput of 41 h-1) of sampling at a flow rate of 6.0 mL/min,an EF of 9.8(higher than 4.9 achieved by conventional elution method) and a detection limit(3σ) of 3.1μg/L-1 were obtained.The precision(RSD,n=11) was 2.2% at 200 μg/L-1 level.When 0.1 ‰(v/v) triethannolamine was used as masking reagent,the recovery rate of Ni in water was from 95.5 %~97.8 %.