Method for washing and separating pieces of a plastics material (P) - coming from containers, bottles, films of plastics - from contaminating material (C), comprising the steps of: a. supplying the pieces of plastics material (P) with the contaminating material (C) and a washing fluid (W) in a washing container ; b. driving a blade stirrer rotating in said washing container , for generating in the washing fluid (W) a turbulent stirring action to achieve a first separation (S1), through mechanical action, of the contaminating material (C) from the plastics material (P), c. removing from said washing container a quantity (Q) of washing fluid (W) containing plastics material (P) and contaminant (C) to send said quantity (Q) to a centrifugal separating unit provided with a rotor, and d. subjecting said quantity (Q), by said rotor, to a centrifugal mechanical action to achieve a second separation (S2), through mechanical action, of contaminating material (C) from said plastics material (P), and to separate a first fraction (F1) consisting of washing fluid and contaminants, from a second fraction (F2) comprising substantially plastics material (P), and e. returning inside said washing container said second fraction (F2) to subject said plastics material (P) to a further turbulent stirring action such as to further separate any possible contaminant still sticking to the plastics, and f. evacuating said first fraction (F1) of washing fluid and contaminants (C) to subject said first fraction (F1) of washing fluid and contaminants (C) to a filtering treatment. and f' . periodically evacuating from said washing container a fraction of heavy contaminants to be eliminated that settle on a bottom of said washing container . a. supplying the pieces of plastics material (P) with the contaminating material (C) and a washing fluid (W) in a washing container ; b. driving a blade stirrer rotating in said washing container , for generating in the washing fluid (W) a turbulent stirring action to achieve a first separation (S1), through mechanical action, of the contaminating material (C) from the plastics material (P), c. removing from said washing container a quantity (Q) of washing fluid (W) containing plastics material (P) and contaminant (C) to send said quantity (Q) to a centrifugal separating unit provided with a rotor, and d. subjecting said quantity (Q), by said rotor, to a centrifugal mechanical action to achieve a second separation (S2), through mechanical action, of contaminating material (C) from said plastics material (P), and to separate a first fraction (F1) consisting of washing fluid and contaminants, from a second fraction (F2) comprising substantially plastics material (P), and e. returning inside said washing container said second fraction (F2) to subject said plastics material (P) to a further turbulent stirring action such as to further separate any possible contaminant still sticking to the plastics, and f. evacuating said first fraction (F1) of washing fluid and contaminants (C) to subject said first fraction (F1) of washing fluid and contaminants (C) to a filtering treatment. and f' . periodically evacuating from said washing container a fraction of heavy contaminants to be eliminated that settle on a bottom of said washing container . <EOS>