The 1,000-kilometer pipeline links Atasu in central Kazakhstan to Alashanku on the Chinese border.
It was built, at a reported cost of $700 million, in a joint venture between the state-run energy companies KazMunaiGaz and China National Petroleum Corporation.
Plans call for the pipeline to eventually carry some 20 million tons of oil annually to energy-hungry China.
Earlier this year, China purchased Kazakhstan's previously Canadian-owned oil producer PetroKazakhstan, whose energy assets are all in Kazakhstan.
RFE/RL Central Asia Report
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