A vehicle frame switchable between an unfolded mode and a folded mode includes a first bar, a second bar, a third bar, and a first pivot unit. The second bar is slidably and pivotably connected to the first bar. The third bar includes a front section and a rear section. The front section is pivoted to an upper section of the first bar. The rear section is pivoted to a lower section of the second bar. The first pivot unit is disposed between the first bar and the second bar. The first pivot unit is operatable to cause the second bar to slide along the first bar so that the vehicle frame is switched between the unfolded mode and the folded mode.