Terri Lynn Rote, who is 55 years old, was charged with first-degree election misconduct, according to the Des Moines Register.
Rote cast one early voting ballot at the Polk County Election Office and another at a county satellite voting location in Des Moines, according to a police report cited by the Register.
In an interview with Iowa Public Radio, Rote said that it was a "spur of the moment" decision, and that she was afraid her first vote for Trump would be changed to one for Hillary Clinton.
"The polls are rigged," Rote told Iowa Public Radio.
Rote was released from jail on Friday after posting $5,000 bond. Her next court appearance is scheduled for Nov. 7, according to the Register.
Trump has repeatedly claimed that the election will somehow be rigged against him.