Mirtha Brock Forbes (born 9 April 1970) is a retired female track and field athlete from Colombia, who competed in the sprint events during her career.

She represented her native country in two consecutive Summer Olympics, starting in 1996.

As well as in two world championships in 1995 and 1997.

Brock won two bronze medals in the relay at the 1995 Pan American Games in Mar del Plata, Argentina.

This biographical article relating to Colombian athletics is a stub.