State investigators are probing a Brooklyn contractor who allegedly unleashed a barrage of racist and sexist messages after he was accused of mismanaging the construction of a luxury condo complex in Carroll Gardens.

Ulgur Aydin is accused of insulting a developer’s Japanese wife, and the couple’s kids, after the architect refused to pay for what he called Aydin’s slipshod work on Gowanus Park — a boutique, 13-unit condo building where units have sold for between $2 million and $3.5 million apiece — public records show.

“Ken how is your old Japanese old wife!!” Aydin allegedly wrote in emails to Kenneth Hudes, an architect who heads the development team for Gowanus Park. “I hear they wash your feet as geisha.”

The emails were included in an April complaint Hudes made about Aydin to the state Division of Human Rights, which agreed in May to look into the matter.

In texts and emails, Aydin referred to Hudes’ “stretched eyes kids,” and asked if Hudes — who is also suing the contractor — celebrated “December 7 when the JPs attacked Pearl Harbor,” according to court documents.

Some of the messages were sent to half a dozen people, said Hudes.

“The utterance of the racial epithets by Mr. Aydin are extreme and outrageous conduct radically outside the bounds of human decency, which were particularly abusive and insulting, thereby resulting in grave harm to me and my business,” Hudes wrote in the complaint to the state.

Aydin’s work on Gowanus Park “was riddled with defects and had to be redone,” Hudes claimed in a Brooklyn Supreme Court lawsuit he filed against Aydin last year.

Aydin also allegedly failed to pay subcontractors and later “abandoned the project,” costing Gowanus Park $120,000 per month in interest, Hudes alleged.

KSK, meanwhile, pursued Gowanus Park for nonpayment of his $1.4 million bill. The case is now in arbitration.

Gowanus Park also wants a judge to bar Aydin “from harassing or using racist language against Gowanus Park or its representatives or their family members.”

Aydin claimed the messages were “false information” and slammed Hudes as “not… normal.”

Aydin’s lawyer, Peter Kutil, admitted the offensive messages were “juvenile stupidity” and claimed Hudes was “blaming the Turkish contractor for his own design errors and omissions.”