  It is shown that the recently proposed preon model which provides a unified
origin of the diverse mass scale and an explanation of family replication as
well as of inter-family mass-hierarchy, possesses a Peccei-Quinn symmetry whose
spontaneous breaking leads to an automatic invisible axion. Existence of the
PQ-symmetry is simply a consequence of supersymmetry and requirement of
minimality in the field-content and interactions, which propose that the
lagrangian should possess only those terms which are dictated by the gauge
principle and no others. In addition to the axion, the model also generates two
superlight Goldstone bosons and their superpartners which are cosmologically
safe.
