Nicki Minaj's brother was just found guilty in his child rape trial ... a case that lasted nearly 3 weeks.
The verdict for Jelani Maraj came in Thursday in Long Island ... he was found guilty of predatory sexual assault against a child and endangering the welfare of a child.
He faces 25 years to life in prison. He'll be sentenced on December 14. Nassau County D.A. Madeline Singas tells TMZ ... "We hope that today's verdict will help the family in the healing process."
TMZ broke the story -- Minaj never testified during the trial -- despite claims she would by her brother's defense team.