The alleged PCP-puffing loser accused of mowing down dozens of people in Times Square, killing a teenage tourist, will likely mount an insanity defense, his lawyer told a Manhattan judge Monday.

Lawyer Enrico DeMarco said he has filed a notice with the court on behalf of Richard Rojas, who did not appear.

Rojas, 26, faces two counts of second-degree murder for the death of 18-year-old Alyssa Elsman, 18 counts of attempted murder, and 38 counts of assault for the May rampage.

If Rojas moves forward with the psych defense, he could be found not guilty by reason of insanity and institutionalized or convicted of a lesser manslaughter charge.

Prosecutors on Monday said they intend for their own psychiatrist to also inspect Rojas.

The unemployed Navy veteran told cops he had smoked PCP-laced marijuana in the hours before he drove his car three blocks down Seventh Avenue, steering into crowds of fleeing pedestrians and terrorizing the Crossroads of the World.

He then smashed his maroon Honda Accord into a metal stanchion and jumped out screaming “I wanted to kill them all,” according to court papers.

Rojas later exclusively told The Post during a jailhouse interview that he had not recollection of the violence.

He is set to return to court in February.