The City of Lincoln Council will serve an eviction notice on Friday to the group of travellers camped on the South Common.
The travellers pitched up in the area on Tuesday and were spotted by a resident walking by.
Another group also set up nearby at the old Peugeot garage on the High Street, and police are attending.
The council will now serve eviction notices to the travellers on Friday.
A spokesperson at City of Lincoln Council described it as “unauthorised encampment” and they will be asked to leave South Common.
This comes just over a week after travellers were told to leave The Lawn after pitching over the weekend.