  It is pointed out that the observed extremely high energy cosmic rays (EHECR)
above $10^{11}$ GeV and the observed baryon asymmetry of the Universe (BAU),
both may have a common origin in baryon number violating decays of supermassive
``X'' particles released from cosmic topological defects (TDs) such as cosmic
strings and monopoles. The X particles produced by TDs in the recent epochs
produce the EHECR, while the BAU is created by X particles released from TDs
mainly in the very early Universe. In this scenario the EHECR is predicted to
contain baryons as well as antibaryons with a small asymmetry between the two.
