Nationals from GCC member states already in Lebanon are advised to stay where they are "to preserve their safety," a statement published late Wednesday by the official Saudi Press Agency said.
Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates are permanent GCC member states.
Lebanon's borders are threatened by civil war in Syria. Fighters from Lebanese resistance movement Hezbollah are fighting alongside pro-government forces in Syria.
GCC Secretary-General Abdullatif bin Rashid al-Zayani said the security alert was issued because instability in Lebanon could threaten the national security of GCC member states, the Saudi Press Agency reported.
Hezbollah fighters helped the Syrian regime retake the town of Qusair from rebel forces this week. The strategic town is near the Syrian border with Lebanon.
Lebanese officials said last month an Israeli airstrike on Syrian targets emanated from Lebanese airspace.
Lebanon broke free of Syrian dominance following the Cedar Revolution in 2005.