Mr Hariri's bloc won June's election but had to form a unity cabinet
Lebanese Prime Minister Saad Hariri is due to hold talks in Damascus for the first time since his anti-Syrian coalition came to power in 2005.
Mr Hariri's office said he would discuss bilateral relations with Syrian President Bashar al-Assad.
This is Ms Hariri's first visit to Syria since the assassination of his father, former Prime Minister Rafik Hariri, in Beirut in February 2005.
Syria has been widely blamed for the attack - a charge denied by Damascus.
Syria was forced later that year to withdraw its troops from Lebanon after 29 years.
Saad Hariri, aged 39, is expected to visit Syria on Saturday afternoon and stay there for several hours.
Last month, Mr Hariri said he was interested in forging relations with Syria based on "clarity and honesty".
"The government wants to raise brotherly ties between Lebanon and Syria to a level in line with the two countries' historical ties and mutual interest," he said before his government received a vote of confidence in parliament.
Lebanon's national unity cabinet was formed after five months of tough negotiations in the wake of June's election, which was won by Saad Hariri's pro-Western coalition.
The government includes two members of pro-Syrian Islamist group Hezbollah.