The riders collided on the B4340 from Aberystwyth to New Cross at about 12:30 BST, on Sunday.
They were taken to Bronglais and Swansea's Morriston hospitals.
Dyfed-Powys Police said they suffered minor to serious injuries. None is believed to be life-threatening.
A group of 10 cyclists were left needing hospital treatment after they crashed into each other in Ceredigion.