The Glendale firefighter suspected of killing his wife with an ax had apparently just found out she was cheating on him “moments” before the gruesome slaying at their North Hollywood home Wednesday, his lawyer said.

Attorney Jose Romero confirmed to The Post that he was retained by the family of the first responder, Andrew Jimenez, to represent him in the homicide case.

“Our office is currently in contact with law enforcement regarding a diary of the decedent, apparently read moments before the homicide, that verified infidelity by the decedent,” the lawyer said in a statement.

“Attorney Jose F. Romero of Romero & Associates has been retained by the family of firefighter Andrew Jimenez, veteran of the Pacific Palisades fire,” he said.

More information about the alleged diary entry was not immediately available.

Jimenez, 45, was taken into custody early Wednesday after flagging down Los Angeles Police Department officers and asking them to conduct a welfare check on his wife, authorities said.

Cops arrived at his home in a multi-family home on Satsuma Avenue and found his wife dead in a bloody scene, FOX11 reported.

Investigators believe she was bludgeoned to death after being repeatedly struck with an ax, the outlet reported.

Police did not immediately publicly identify Jimenez or say what, if any, charges he was facing.

Photos on social media show Jimenez married Mayra Lopez Jimenez in November 2014, with images showing the then-lovebirds embracing.

The website “territiestheknotweddings.com” showed the 46-year-old worked for the nuptials company as an ordained minister before her tragic death.

Her hubby was promoted from paramedic to firefighter by the Glendale Fire Department in June 2024, according to social media posts.

“May God watch over him and guide him as he continues to serve the people and the community,” a woman who identified herself as the suspect’s aunt posted on Facebook at the time, along with images showing him beaming while holding a diploma in front of a fire truck.

Investigators believe Lopez Jimenez, who was not breathing when cops arrived, was bludgeoned to death after being repeatedly struck with an ax, FOX11 reported.

Her husband was taken in for questioning — and allegedly confessed to the gory slaying, the TV station reported.

He was subsequently arrested. Police had not publicly released his name or announced charges against him later Wednesday.

Investigators were spotted removing paper bags, apparently containing evidence, from the home. One detective was also spotted taking rifles out of the home and putting them in a truck.

Several family members, including the victim’s brother, were spotted at the scene moments before the CSI crew entered the unit, according to sources.

The City of Glendale said Jimenez, a  member of the department since 2008, had been placed on immediate administrative leave.

“Our condolences are with the victim’s family and loved ones,” said Fire Chief Jeff Brooks.

“We are prepared to support those impacted by this tragedy, and we are also ensuring our firefighters and staff have access to support resources as they process this loss.”