The discovery was made at Primrose Valley, a community park and recreation ground in Halton.
West Yorkshire Police said:
"At 11.17am today (31/8), police were called to Primrose Valley, Primrose Lane, Halton, where the body of a man had been found.
"The man has not yet been identified and enquiries are ongoing into the circumstances surrounding his death."
It is not yet known if the circumstances are suspicious.
The park has a bowling green, tennis courts and a football pitch.
The incident comes only a day after the body of missing Leeds student John Paul Awi was found in woodland near his home in Stanks.