Abstract: Method for destroying aerosol cans providing for their complete emptying, recovery, separation of various elements contained without losses, and the devices, automatic or not, for implementing the destruction method as well as the automatic piercing machine. The invention is related to the industrial sector of recovery and valorisation of waste products, the innovation of the method according to the invention allowing to pierce the aerosol can by means of a hollow needle (2) allowing to transfer the contents into a low pressure separation vat (8) making both housings, the aerosol can and the vat (8) to communicate, the invention using the resulting expansion in order to seperate the gases from the liquids, said gases thus expanded being sucked, compressed means of a compressor (13), liquified by an air-condenser (15) from where they are transferred into storage vats for treatment or reuse, the recovered liquids at the bottom of the vat (8) being transferred for reconditioning, treatment or destruction.