The three a Bosnian, a Macedonian and an Italian had been working for an Italian construction company when they were kidnapped on Saturday in the western town of Zuwara, near the Tunisian border.
Officials from Macedonia and Bosnia said Libyan authorities found the Macedonian man, identified as 29-year-old Miljazim Gafuri, today along with Bosnian engineer Petar Matic.
A Libyan security official said the two were found in Tripoli and had been returned to Zuwara, where they were being debriefed.
The Libyan official, speaking on condition of anonymity because he was not authorised to speak to reporters, said the search for the Italian engineer was still underway but a suspect is being interrogated in the case.