Tekashi 6ix9ine was “startled” by an unwelcomed family reunion in court Wednesday with his estranged father, his lawyer told The Post.

The Brooklyn-born rapper appeared stunned by the sight of his father, who is also named Daniel Hernandez,during his sentencing in Manhattan federal court.

“He hasn’t seen him since the third grade. It’s too little too late,” his lawyer Lance Lazzaro told The Post. “He was definitely startled by that.”

As he prepared to read a letter to the judge, the 23-year-old addressed the awkward family reunion with his 58-year-old father.

“I took one glance in the audience … Man, I don’t even know,” Tekashi told the court. “Is this a f—ing joke, with everything that I go through?”

The rapper has claimed he hasn’t seen the man since his mother kicked the elder Hernandez out of the house over his supposed drug use.

His father raised his hand to speak on behalf of his son at the sentencing, but the judge seemed to take Tekashi’s side in the family feud.

“It’s way too late to show up and speak on his behalf. You squandered that right many years ago,” Manhattan federal Judge Paul Engelmayer told the dad.

The elder Hernandez said that he wanted to show support for his son — and even tell him that he loved him.

“I’m trying to look out for him,” he told The Post. “I want to tell him I love him.”

Outside the courthouse, the Hernandez patriarch said that he’s a fan of his son’s tattoos and “loves” his music, though he couldn’t name a favorite song.

He declined further comment saying, “No money, no cigarettes.”

The “Gummo” singer was sentenced to two years behind bars Wednesday for racketeering and other charges from his time as a member of the Nine Trey Gangsta Bloods.