Sheet feeding device and image forming apparatus

The sheet feeding device includes a straight sheet feeding passage, and plural sheet feeding sections. Each sheet feeding section includes a container containing a stack of sheets; a driving rotor; a first driven rotor contacting the driving rotor to form a first nip; a feeding member feeding the sheet from the container toward the first nip; and a second driven rotor contacting the driving rotor or the first driven rotor to form a second nip at the junction of the sheet feeding section and the sheet feeding passage. Only the sheet feeding section on the extreme upstream side has a curved guide instead of the second driven rotor to directly feed the sheet to the second nip of the adjacent sheet feeding section so that the sheet at the curved guide has greater curvature radius than the sheet fed from the other sheet feeding sections toward the second nip thereof.