To provide a vehicle assembly line which can achieve efficient execution of assembling work of vehicle underbody components to each vehicle body.

A vehicle assembly line 1 includes a plurality of floor friction carriers 10 that convey vehicle bodies 2 along the line with the vehicle bodies supported, and the vehicle underbody components are assembled to the vehicle bodies 2 supported by a plurality of the floor friction carriers 10. A plurality of the floor friction carriers 10 support the vehicle bodies 2 in such a manner that the longitudinal direction of each of the vehicle bodies 2 intersects perpendicularly the direction of conveying the vehicle bodies 2.