The present invention relates to a polysiloxane-polycarbonate copolymer using a hydroxyl terminated polysiloxane mixture, and a method for producing same, and more specifically, to: a polysiloxane-polycarbonate copolymer which includes hydroxy-terminated polysiloxanes of chemical formulae 1 and 2 in a specific weight ratio as repeating units, and thus exhibits excellent transmittance and low-temperature impact strength compared to the case of using either of the hydroxy-terminated polysiloxanes by itself, and in which the overall production yield of the raw material polysiloxane is improved, such that the polysiloxane-polycarbonate copolymer is excellent in terms of economics; and a method for producing same.