The army said four of the launchers discovered had rockets inside them and were ready to be fired.
Experts were working to dismantle the weapons that were discovered near the village of Qlaileh, south of the port city of Tyre, the army said.
Israel has moved troops toward its northern border with Lebanon in recent days, suggesting the Israelis anticipate a second front as they tackle Hamas further south in Gaza.
Hezbollah's relationship with the Lebanese armed forces is complicated but the militant group is the stronger of the two and could drag Lebanon into a conflict without a government decision, as it did in 2006.
Locations:
Qlaileh, Tyre, Israel, Lebanon, Gaza, Lebanese