Raúl Alberto Cubas Grau (born 23 August 1943) is a Paraguayan politician and electrical engineer who served as the 45th President of Paraguay from 1998 until his resignation in 1999.

As a result of these days of social unrest, which came to be known as the Marzo Paraguayo, Cubas resigned and was succeeded by the president of the Senate, Luis González Macchi.

In August, however, three days after his inauguration, Cubas reduced Oviedo's sentence to the time already served, effectively releasing him from jail.

Despite an order from the Paraguayan Supreme Court in December 1998, Cubas refused to send Oviedo back to jail.

Seven people were shot to death and dozens were injured when the demonstrations turned violent, in what became known as the Marzo paraguayo ("Paraguayan March").

Facing certain conviction and removal from office by the Senate, Cubas resigned on March 28, 1999, while Oviedo fled to Brazil.

Oviedo returned to Paraguay in 2004 to face his charges both for the 1996 coup attempt and the killing of protesters during the Marzo paraguayo, and was immediately imprisoned.