After previously reporting the discovery of five tunnels, the Israeli military said another had been found yesterday, 55 metres deep and reaching "a few tens of metres" into Israel from a point 800 metres within Lebanon.
Lt Col Conricus said the sixth tunnel started in the border town of Ramyeh and was 55m (180ft) deep and 800m (2600ft) long.
Hezbollah and Israel last fought a war in 2006.
The announcement that the operation is ending comes as military chief of staff Gadi Eisenkot steps down at the end of his term.
The operation, made public by Israel in early December, had stirred fears on both sides of a flare-up.
"Overnight, the air force also attacked on the southern front against Hamas targets in Gaza and this morning we announced the exposure of an additional tunnel, a main tunnel, perhaps the most important, that crossed the border into our territory".
"According to our intelligence and our assessment of the situation there are no longer any cross-border attack tunnels from Lebanon into Israel".
Last month, Israel launched an operation to detect and destroy what was described as a vast network of Hezbollah tunnels, and officials say the latest discovery brings the mission to an end. In 2018 alone, he said Israel's air force dropped 2,000 bombs in Syria.
In the wake of the tunnel discoveries, Israel has asked the worldwide community to impose tough sanctions on Hezbollah and launch action against its state-within-a-state operation in Lebanon. Conricus says the United Nations peacekeeping mission, known as UNIFIL, had been updated on the latest development.
While the Syrian government repeatedly accuses the Jewish state of constantly violating its sovereignty and aiding the terrorists by their raids in the country's airspace, Eisenkot claimed the Israeli actions are justified - and that, anyway, neither Damascus nor Tehran can do anything about it.
The military said its forces will remain in the border area to monitor any further underground activity.
Israel in recent years has carried out hundreds of airstrikes in Syria against targets linked to Iran, which alongside its proxies and Russian Federation is fighting on behalf of the regime of Syrian President Bashar Assad.
Israel has long called for a crackdown on the Iran-backed Hezbollah, a heavily armed mini-army that is believed to possess an arsenal of some 150,000 rockets that can reach almost all of Israel.