Caleb Flynn, 40, was convicted of aggravated murder and multiple related charges, including felonious assault and tampering with evidence, in the death of Ashley Flynn, 37, a schoolteacher and volleyball coach.
Prosecutors said Flynn shot his wife twice in the back of the head while she slept at their home in Tipp City, a suburb north of Dayton, on 16 February this year, then staged a home invasion and claimed burglars were responsible. The couple's two daughters were home when police arrived.
Flynn wept in court as the judge read the guilty verdicts, shaking his head and closing his eyes. He faces up to life in prison.
During the trial, prosecutors presented evidence including police body camera footage and data from Flynn's iPhone and Apple Watch. The defense called no witnesses.
Flynn appeared on American Idol in 2013, telling viewers how his wife had encouraged him to chase his dreams on the singing competition. He sang before judges Mariah Carey, Randy Jackson and Nicki Minaj but did not advance to the main competition in Hollywood.
The jury deliberated for less than three hours before returning its verdict. Sentencing has not yet been scheduled.