"Swiss citizens living in Syria were given due notice that the embassy would be closed and consular services transferred to Beirut," the Swiss foreign ministry said in a statement, citing "reasons of security".
On February 15th, Switzerland announced its intention to close the embassy, without a giving specific date.
The Swiss ambassador to Syria was recalled to Bern in August 2011 for consultations and never returned to Damascus.
Then in late November, the foreign ministry urged Swiss nationals to leave Syria as soon as possible.
Some 150 of the 180 Swiss registered with the embassy are still in Syria.
The vast majority of Swiss citizens in Syria - 147 people, or nearly 80 percent - are dual nationals.
Some 7,500 people have been killed in Syria since the start of the crackdown in March 2011, according to the UN.
Syria on Wednesday refused to let UN humanitarian chief Valerie Amos enter the country to assess the growing crisis blamed on the government's deadly clampdown on protests, the UN official said.
The refusal came as the UN Human Rights Council in Geneva was poised to decide Thursday on a draft resolution calling on Syrian authorities to grant "unfettered access" to UN and humanitarian agencies to enter all areas.