Police were called to the Club Cars private hire office, in Driver Terrace, New Wortley, at about 2am today.
Three men - including one armed with police believe was a handgun and another carrying a hammer - threatened staff after bursting into the office.
They also stole a cash box containing money, a handbag, mobile phones and keys from the staff.
The offenders, who had their faces covered, then fled towards the Clydes.
One of the men has been described as being black, police said.
Detective Inspector Dave McDougal, of Leeds District CID, said: “This was a frightening experience for the members of staff involved and we are carrying out extensive enquiries to identify the people responsible.
“We would like to hear from anyone who was in the area and witnessed anything suspicious or anyone who has any information that could assist the investigation.”
Anyone with information is asked to contact Leeds District CID via 101 quoting crime reference 13180554149 or call the independent charity Crimestoppers anonymously on 0800 555 111.