Jeremy R. Bledsoe, 32, was set to go on trial in February for the murder of Kathryne Bledsoe, 31, before his court appointed attorney, Sidney Tongret, requested a change of plea hearing.
Putnam County Prosecutor Tim Bookwalter emphasized there was no plea agreement in place.
At Thursday's hearing, Bledsoe, under Tongret's questioning, admitted he killed Kathryne.
Bledsoe's sentencing is set for May 5.
Bledsoe told Circuit Court Judge Matt Headley he understood that by pleading guilty, he waived the right to a jury trial and certain other constitutional rights.
Questioned by Bookwalter, Bledsoe said he used a shotgun to shoot Kathryne and that he bought the ammunition the day before with the intention of killing her. He further stated he considered killing her the night before, but did not because his kids were sleeping with her on the couch.
"I did (consider killing her), but my kids were sleeping with her," Bledsoe said. "I didn't want to wake my kids up with gunfire."
Instead, he said he shot her the next morning when she was dressing after a bath with the two youngest of their three children. The children were in a different room, and their oldest child was at school.
"I didn't say anything," Bledsoe said. "I just picked up the gun and shot her."
Bledsoe said he killed Kathryne because she was planning to leave him.
"She was going to leave and take my kids with her and go back to her ex-boyfriend," Bledsoe said. "And I couldn't handle that."
Bookwalter requested copies of any psychological examinations Bledsoe has undergone, as he assumes the defense will cite them as a mitigating factor at the sentencing. Tongret said his client might undergo further evaluations prior to May 5.
Bledsoe could be convicted to a maximum of 65 years in prison. Bookwalter said the case did not meet the criteria necessary for the death penalty.
Felony murder carries a minimum sentence of 45 years.