Keith Davies, 56, from Troedyrhiw, has not been seen since he left his home at about 12:00 GMT on Saturday.
South Wales Police had appealed for information following his disappearance.
On Monday, the force confirmed a body has been found but has not yet been formally identified. Mr Davies' family has been informed.
A body has been found by police in their search for a missing man from Merthyr Tydfil.