"The visit is taking place in the context of an increasingly active Russian-Iranian dialogue of late that reflects the high level of mutual understanding between Moscow and Tehran," Russia's foreign ministry said in a statement Saturday.
The two countries are on increasingly good terms and Russia helped steer through the landmark July agreement with world powers over Iran's nuclear programme.
Moscow is hoping that its firms can benefit from the nuclear deal, which should see economic sanctions lifted on Tehran.
A flurry of diplomacy saw the foreign minister of Saudi Arabia hold talks with Lavrov in Moscow this week, along with representatives of the Syrian opposition.
Russia wants a broader grouping to cooperate in the fight against the Islamic State jihadists that have seized swathes of territory in Iraq and Syria, expanding from a US-led coalition to include the Syrian government and its allies.