A Bronx pervert convicted of sexually abusing a girl starting when she was 5 just landed 15 years behind bars — but his lawyer blasted the sentence as “very cruel” for a 64-year-old man.

Alberto Hernandez was slapped with the prison term Friday by Bronx Supreme Court Justice Steven Hornstein, who also sentenced the sicko to 10 years of post-release supervision and said he must register as a sex offender when he gets out.

Hernandez was convicted by a jury in June after a six-week trial of one count of course of sexual assault against a child and one count of endangering the welfare of a child, according to the Bronx District Attorney’s Office.

He carried out his “heinous” abuse from June 2011 through June 2016 on a child attending his wife’s now-defunct home daycare business, called Maria Cortez Daycare, in Kingsbridge Heights, prosecutors said.

The victim — now 18 — began attending the daycare when she was 9 months old. But her demeanor began changing when she was 5 after Hernandez launched his depraved attacks on her inside his home, prosecutors said.

Alberto Hernandez
Alberto Hernandez was sentenced to 15 years in prison for sexually abusing a young girl attending his wife’s daycare.

The child was abused until she was 11, but she didn’t come forward until three years after leaving the daycare and suffering emotionally and mentally for years, prosecutors said.

“The defendant’s heinous acts caused irreversible harm to a little girl who will now suffer for a lifetime,” DA Darcel Clark said in a statement. “The defendant used his wife’s home daycare business to gain access to the child.

“No one should ever have to endure such violence and my office will make sure that anyone who commits such harm against a child will face many years in prison,” Clark said.

But Hernandez’s lawyer, former judge Armando Montano, told The Post on Monday he plans to appeal the sentencing and verdict, claiming his client did not get a fair trial and calling the penalty “very cruel,” given the convict’s age.

Alberto Hernandez
The 64-year-old defendant was convicted by a jury in June after a six-week trial.
Christopher Sadowski

“I don’t think that the jury verdict was justified in this case. I still totally believe in my client’s innocence,” Montano said.

Montano said the judge didn’t allow evidence showing inconsistencies in the victim’s story and didn’t let him show she wasn’t a credible witness. 

“She made several lies when she made the outcry” about the sexual assaults, Montano said.

“This was not a fair verdict, and hopefully the appellate court will do the right thing, and hopefully this will ultimately prevail,” the lawyer said.