According to official court documents obtained by TMZ.com, the former One Direction star - who shares one-year-old daughter Khai with Gigi - pled no contest to the four criminal charges of harassment against him.
The papers state that the row began at Zayn and Gigi's home in Pennsylvania on 29 September (21), when he is said to have called Yolanda a "f**king Dutch s*ut" and ordered her to "stay away from (my) f**king daughter."
He then apparently "shoved (Yolanda) into a dresser causing mental anguish and physical pain." Zayn denies making physical contact with the model.
In addition to the harassment of Yolanda, Zayn is also accused of harassing Gigi as he apparently said to her at one point "strap on some f**king balls and defend your partner against your f**king mother in my house."
A security guard was present at the time, with Zayn allegedly trying to fight him and screaming at him, "Get the f**k out of my f**king house copper."
Zayn has been fined for the harassment and is on 90 days' probation for each count - making a total of 360 days. He will also have to complete an anger management class, and a domestic violence programme.
In addition, he is forbidden from making contact with Yolanda or the guard.
Zayn and Gigi's relationship is said to have come to an end around the time of the argument.
If Zayn abides by the rules set by the judge, probation could be terminated after six months.