On Monday, January 11, the 96-year-old man was at his home in Hazelmere Road, Fulwood, when two men knocked at his door.
They stated they knew him before he has allowed them inside, and then they pressurised him to hand over £200.
The man became concerned and asked the pair to leave. They left taking the keys to the address but no money was handed over.
DC Corina Barton from Preston CID said: “These men have targeted a vulnerable, elderly gentleman who should feel, and be safe in his own home.
“This was an extremely distressing incident for the victim. The offenders may have approached other elderly residents in the area and I am keen to hear from anyone who may have information that could assist us to come forward.”
One of the men is described as white, 5ft 4ins, around 40 to 50 years old, of stocky build and was wearing a black jacket and dark trousers.
The second is described as white, 6ft, around 30 years old, of slim build and was wearing a light coloured jacket.
Anyone with information can call police on 01772 209749 or 101 quoting incident reference 894 of January 11, 2016.
Alternatively Crimestoppers can be contacted on 0800 555 111 or online at https://crimestoppers-uk.org