Turkey provides military backing to the Tripoli-based Government of National Accord (GNA), which has been trying to fend off an offensive by forces of Libyan National Army (LNA) commander Khalifa Haftar to the east.
Last year the GNA and Turkey signed a military cooperation deal and Turkey has since sent troops and allied fighters of the Syrian rebel group, the Syrian National Army.
Ankara has so far stressed its forces were not fighting in Libya but rather providing coordination to the GNA. Erdogan said on Saturday that Turkey had "several martyrs" in Libya, and on Tuesday he clarified two had died.
Later on Tuesday, a military source in Haftar's LNA said it had shot down a Turkish drone, but the GNA did not confirm that, saying only that "what was heard" was the falling of missiles.
"We have two martyrs of ours there (Libya)," Erdogan told a news conference in Ankara.
"Those going from Syria from the Syrian National Army have a common goal. They are there within the framework of these common goals ... Our brothers who are with us in Syria see being there with us as an honor," Erdogan added.
The Syrian National Army is a Turkey-backed rebel group fighting against pro-Syrian government forces in northern Syria.
On Sunday, the LNA said they had killed 16 Turkish soldiers in recent weeks. Since the deployment of Turkish soldiers and sophisticated equipment to the GNA, the LNA has lost some of its gains. The LNA is backed by the United Arab Emirates, Egypt and Russia.
At a summit in Berlin last month, world powers agreed that hostilities must stop in Libya while a political process takes place. Ankara has since accused Haftar of violating the ceasefire, saying its guarantees regarding a United Nations arms embargo to Libya were dependent on a durable truce.
Ceasefire talks between Libya's warring sides, which resumed last week after a pause over clashes on the ground, were in the "right direction," the U.N. envoy for Libya said on Friday. But lawmakers based in areas under Haftar's control said on Monday they would not participate in talks with politicians allied to the GNA.