The incident came to light when neighbours grew suspicious as the house remained locked from inside even after dawn and knocked on the doors but received no response, police said.
Immediately, they informed the police who rushed to the spot and forcibly opened the door. They found the man hanging from the ceiling while his wife was lying in a pool of blood.
Police said the old man had slit her throat.
There used to be frequent quarrels between the couple, whose children were living separately in the town, they added.