The train will travel across the Chinese border via the Xinjiang Uyghur Autonomous Region before travelling through Kazakhstan and Turkmenistan on its way to Tehran, the Iranian capital, China News Service reported.
The train, that left China on January 28, will take 14 days to complete the more than 10,000 kilometer journey from Yiwu, a city which is home to more than 4,000 Middle Eastern businessmen.
It is also the arrival and departure point for freight trains connecting China and Madrid.
The train is part of China's Silk Road plan, increasing influence in Eurasia through economic agreements with countries in the area.
After meetings with Chinese President Xi Jinping on January 23, Iranian President Hassan Rouhani revealed the Islamic republic plans to increase its trade with China ten-fold over the next decade, GB Times reported on Friday.