The invention relates to a method for the biometric characterisation of a user by the recognition of his/her hand. The invention also relates to a discrimination method that uses the previous characterisation to establish whether the hand of a user corresponds to the hand used in the characterisation. The invention further relates to a system that can implement said methods and provides a result. One result of this system is either the identification of the registered user matching the user that is the object of the recognition, or the non-identification of any of the registered users.