Tyga Fights Club Owner ... Eyewitness Says Gun Drawn (VIDEO)

Tyga pissed off a Swiss club owner so much, the guy chased him outside and started a fist fight with the rapper and his entourage ... and Kylie Jenner had a front row seat.

Tyga was scheduled to play a show at Envogue Genève, a club in Geneva, Switzerland. According to our sources, Tyga was supposed to play for an hour ... but he showed up super late and only performed for about 10 minutes.

Tyga left the club around 4 AM and got in his car with Kylie. The enraged owner was hot on Tyga's heels, running out of the club, yelling for Tyga ... a fight then broke out.

At that point Tyga got out of the car to join in the fracas, but an eyewitness says someone in the owner's posse flashed a gun. That was apparently enough for Tyga to make a hasty retreat, leaving his bodyguards behind.