Ramirez died of natural causes, with some reports citing Hepatitis C, at Marin General Hospital in Greenbrae, Calif. He was 53 years old.
He was memorable caught by an angry mob in East L.A., after cops lifted a fingerprint from a car and identified him, and plastered his mug shot everywhere.
In 1989 Ramirez was sent to San Quentin's death row after being convicted of 13 murders, five attempted murders, 11 sexual assaults and 14 burglaries.
According to San Quentin State Prison spokesman Lt. Sam Robinson, only 13 condemned inmates have been put to death. There are currently 735 offenders on California's death row.