Enter Transaction Code SPRO in the SAP Command Field
In the next screen, Select 'SAP Reference IMG.
In the next screen , 'Display IMG' Follow the menu path Controlling->Profit Center Accounting -> Assignments of Account Assignment Objects to Profit Center ->Assign Cost Centers
In the next screen, Enter the cost center to be assigned to a profit center
In the next screen , Enter the profit center to which the cost center is assigned
Press 'Save' button from the SAP Standard toolbar , for the saving the changes.