Her Grave Mistake is a 1914 American silent Western film featuring Lon Chaney and Murdock MacQuarrie. Very little is known about who wrote or directed this film. The film is now considered to be lost.

Plot

Roger Grant, foreman of the "Circle S" Ranch on the Mexican border, is engaged to Isabel Norris, the old ranch-owner's daughter. Grant receives word from the national guard warning him that there may be an attack by Mexicans on the pumping station at the reservoir and that he should arm his cowboys to protect it until troops can arrive. Nunez, a Mexican spy, breaks into the ranch house to steal the letter that Grant received.