It departed from London on April 10 and reached Yiwu on April 29 on the world's second-longest route; the longest is the China-Madrid link.
The journey, 30 days shorter than transit by ship, took two days longer than expected.
First UK-China freight train completes 12,000km journey
Successful run, but costs unclear
East Wind, the train, was loaded with whiskey, pharmaceuticals, baby milk and machinery on the journey.
Its locomotive and carriages had to be changed en route due to larger gauges in the former Soviet Union.
However, it is unclear how much the project cost; whether it makes economic sense remains to be seen.
Pros and cons of the train route
A train route will bring in more convenience and flexibility than sea routes.
"It can make multiple stops, allowing for the pick-up and offloading of cargo along the way. Rail transport is also less affected by adverse weather conditions," said He Tianjie of Oxford Economics.
But it has much less carrying capacity: compared to cargo ships' 10,000-20,000 containers, East Wind can carry just 88.
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China on expansion drive
China is on a drive to strengthen trade links with western Europe on a modern-day "Silk Road" route; in 2013, it launched the "One Belt, One Road" initiative.
Beijing is already connected via freight train to Duisburg and Hamburg in Germany, Europe's largest economy.
In 2016, 1,702 trains journeyed to Europe, more than double the previous year's figure.