Lancashire Police were called to the property on Cann Bridge Street in the village of Higher Walton on Saturday. Police forced entry to the building and found a man and woman dead inside. Police are treating their deaths as suspicious.
Lancashire Constabulary said in a statement: "We were called at 1.40pm today to a concern for the safety of the occupants of a property on Cann Bridge Street, in the village of Higher Walton.
"Officers have forced entry and sadly found a man and a woman deceased inside.
"Their deaths are being treated as suspicious and a scene is currently in place.
"No arrests have been made at this stage. Enquiries are very much ongoing.
"Reassurance patrols have been stepped up in the area."