Authorities say the man had a knife when he broke into the home on the Lang Hill road about 9:00 p.m. Thursday.
The man, who was wearing a red bandana over his face, demanded money.
The woman alone in the house gave the man an undisclosed amount of money, then he restrained her with duct tape.
Deputies are in the process on interviewing people who may know something about the incident.
If you have any information, you’re asked to call the Somerset County Sheriff’s Department at 1-800-452-1933.
You can also use the anonymous tip line at 474-0230.