West Yorkshire Police were called to an address in Pavilion Gardens at about 9.30pm last night (Monday).
A spokesman said: "Enquiries into the incident are continuing today, but it is believed that a group of masked males entered the rear of the property and took cash and jewellery after threatening the occupants.
"The males, some of whom were reported to have weapons, have then left the scene."
Nobody was hurt during the robbery.
Anyone who witnessed any suspicious activity in the area is asked to contact Bradford District CID on 101, quoting crime reference 13170481418.