The present invention relates to a delamination method for recovering constituents of a paper-based multi layered laminated packaged waste. The method comprises using of a mixture of inorganic bases to separate the constituents of the packaged waste and recover paper, plastic and/or aluminium components separately. The paper can be recovered as pulp, the plastic can be recovered as is, and the aluminium can be recovered as a water soluble salt. The delamination method of the present invention is also effective on cardboard-based multi layered laminated packaged waste.