Abstract: A mobile type auto-doffer for ring spinning machines and the like consists of a doffing device and a donning device with mechanisms similar to those of a doffing device. The operation for doffing full bobbins may be carried out by utilizing the doffing device, and the operation for donning fresh bobbins may be carried out by utilizing the donning device. During the doffing operation, a plurality of full bobbins is simultaneously transported from the spindles to the pegs disposed between the spindle rail of the spinning machine and the surface of the floor of a spinning plant. During the donning operation, the same number of fresh bobbins as that of a full bobbins is simultaneously transported from the pegs to the spindles. Both of the above-mentioned ways of transporting bobbins may be carried out by moving the full bobbins or the fresh bobbins along separate vertical passages, respectively, i.e., one passage being disposed farther from the row of spindles than the other passage.