The scene where the grim discovery was made remains sealed off this morning.
The victim appears to have sustained a head wound and gardaí suspect he may have been shot.
Gardaí are trying to identify him and are checking on the whereabouts of a number of people to rule them out, including a significant criminal in this area who has not been seen since yesterday afternoon.
They may need to rely on DNA for identification.
Gardaí are also appealing for any information in relation to a navy Toyota Corolla with the registration 05-CW-2225 and said the car was sold on 13 November.
Detectives believe it is likely the victim got into the car with a person or people he trusted and was driven to the place where his body was discovered.
The car appears to have been set on fire in an attempt to destroy evidence.
The man’s body has been removed from the scene and a post-mortem examination will be carried out by Locum State Pathologist Dr Heidi Okkers.
Gardaí have appealed to any motorists who were in the Mount Andrew Rise area last night and who may have dash cam footage to contact Lucan Garda Station on 01 666 7300 or the Garda Confidential Line on 1800 666 111.