Abstract: Extraction of cyanide from leaves of phyllostachys pubescens by steam distillation method has been performed.Cyanate ion was well determinated by ion-selective electrode using H₃BO₃ as ionic strength agent at the temperature from 18 ℃ to 25 ℃ with medium stirring speed in the pH was 12 alkaline medium.Under the optimum conditions，the measured scope ranged from 0.1 μg·g^-1 to 10.0 μg·g^-1 with the relative standard deviation of 1.1%～4.2% (n=6).The recoveries of CN- ranged from 96.0% to 102.0%.The method has the advantages of simple operation，high sensitivity and high sample throughput.The method has been applied to the determination of cyanate ion and the results are satisfactory.

Key words: steam distillation, ion-selective electrode, phyllostachys pubescens, cyanide