The invention pertains to mobile telephones and can be used during telephone conversations while, for example, operating a mode of transportation. The universal hands-free unit for mobile telephones contains the main module containing a speaker and control electronics, a holder for the mobile telephone, a microphone, an attachment module, and a changeable connection module for electrical connection of the control electronics with the electrical circuits of the mobile telephone. The holder of the mobile telephone is constructed in the form of two plates oriented parallel to each other at a distance L which may be changed by moving at least one plate relative to the other plate with the help of a mechanism located in the body of the main module. A fixating bracket attached to each holding plate, each fixating bracket is made in the shape of a base with several parallel resilient fins.