Mr Brahimi will hear Turkey’s perspective on the raging crisis from Foreign Minister Ahmet Davutoglu.
His visit comes just days after five Turkish civilians were killed in shelling from across the Syrian border.
Earlier this week, Turkey intercepted a Syria-bound plane amid reports it had Russian-made defence equipment aboard.
Syria has dismissed the claim as a lie, challenging Turkey to show any evidence.
And in Syria itself, activists said on Friday that rebel fighters had seized a government air defence base near the embattled north-western city of Aleppo.
The claim has not been independently verified.
‘No obvious plan’
Mr Brahimi is due to meet Mr Davutoglu in Istanbul later on Saturday.
Turkey may not be at war with Syria, but it is now increasingly involved in its neighbour’s conflict, the BBC’s James Reynolds in Turkey reports.
The government of Syrian President Bashar al-Assad accuses Turkey, along with Saudi Arabia and Qatar, or arming the rebels – a claim denied by the those countries.
Mr Brahimi’s visit comes a day after he met senior Saudi officials in the city of Jeddah.
Saudi Deputy Foreign Minister Prince Abdel Aziz bin Abdullah was quoted as urging for “an immediate halt to the bloodshed of the Syrian people”.
However, the envoy’s visit to the region carries no immediately obvious peace plan, our correspondent says.
He adds that UN Secretary General Ban Ki-moon has suggested Mr Brahimi may head to Damascus next week if his meetings in the region go well.
Source: BBC News