Objective To establish a simple,accurate and sensitive method for determination of cyanide in drinking water. Methods By means of using flow injection analysis instrument, the cyanide in drinking water was determined on-line. Results The data obtained by this assay accorded with Beer's Law, the range was 2.0-50.0 ?g/L, r≥0.999, the detection limit, relative standard deviation and recovery rate were 0.23 ?g/L, 2.5%-3.8% and 94.9%-98.7% respectively. The sampling frequency was 20 samples per hour. Conclusion The method for determination of cyanide in drinking water employed in the present paper is simple, accurate, sensitive and suitable for the analysis of large number of water samples.