The objective of this study was to triboelectrostatically separate artificial plastic mixture of three kinds of components (i.e. ABS, PS and PP mixture). The mixture is charged by friction in tribo-cyclone. After a given period of time inside the tribo-cyclone, the charged plastic flakes fell down freely through a horizontal electric field into collection bins. The DC electric field of maximum 400 kV/m is created by using two parallel plate electrodes made of Cu and having a given cross-section configuration. The plastic flakes of the mixtures are drawn to either positive or negative electrode according to the polarity of the charge and are separated by falling in different bins. The purification of three-component mixture is accomplished by a two-step triboelectrostatic process. Separation tests in a batch laboratory triboelectrostatic separator showed that the efficiency of the separation is strongly depended on tribocharging time, air inlet velocity, and electric field strength. Products of ABS, PS and PP with a grade of 92.1%, 84.9% and 90.0% respectively have been achieved with recoveries above 73.0%.