Some 793 km of the trunk line are in Myanmar, while the rest is in China.
It is expected to send 12 billion cubic meters of natural gas annually to Myanmar and southwest China, which will reduce coal consumption by 30.72 million tonnes per year, the China National Petroleum Corporation (CNPC) said.
Wu Hong, general manager of the CNPC's pipeline construction department, said the China-Myanmar gas pipeline will linked with the pipeline that sends gas from China's remote northwest to the east coast, hence greatly increase the reliability of supply to customers, particularly in case of emergency, state-run Xinhua news agency reported.
The Myanmar section of the gas pipeline started to deliver gas to China in late July.
The CNPC is the parent company of China's top oil and gas producer -- PetroChina.