Emergency services were called to the farm property in Terregles near Dumfries at around 12pm on Friday.
The body of a man was discovered and officers also found a chemical spillage on the floor of the cottage.
His death is currently being treated as unexplained.
A Police Scotland spokesman said: "An exclusion zone of 100 metres was put in place as a precaution.
"A number of roads have been closed off in the surrounding area."