Von Miller is finally opening up on his domestic violence arrest ... adamantly saying the allegations against him are "100 percent false."
The Buffalo Bills superstar sat in front of media members for over 10 minutes on Thursday to explain his side of the story ... roughly one month after he was thrown behind bars for allegedly roughing up his pregnant girlfriend during a bye-week argument in Dallas.
Miller repeated over and over again that he did not put his hands on his GF -- saying emphatically, "All of it is incorrect. All of it is untrue.