A multitude of emergency services raced to the towns Argyle Street on Monday night, and within a short space of time emergency response vehicles,Ambulance, Police,CID and forensic officers descended on the street.
A neighbour of the flat has confirmed on social media police have stated to them that the boy who is 4 years old boy is deceased as well as the father.
Forensic officers remained at the scene till late on Tuesday night with a forensic tent erected at the close whilst further investigations took place.
Post mortem examinations will be carried out in due course and a report sent to the procurator fiscal.
A police Scotland spokesperson said: “We received a report of concern for a man and a child at a property in the Argyle Street area of Paisley around 8pm on Monday, May 15.
“Officers attended and a man and a boy were found dead within the property. The deaths are currently being treated as unexplained and post mortem examinations will take place in due course.
“At this time, we have no information to suggest anyone else has been involved. A report has been sent to the procurator fiscal.”