This is according to a report in China Petroleum New, a CNPC-run paper.
(READ MORE: South Sudan oil output steady)
Oil is the main source of cash for South Sudan, but output has dropped due to conflict and ageing fields. Fighting between rebels and the government has damaged some fields.
CNPC's engineering and services team will work with oil producers in South Sudan and also conduct training on technologies to enhance oil recovery (EOR), the report said.
Main investors in South Sudan include CNPC, parent of PetroChina, Malaysia's state-run oil and gas firm Petronas and India's ONGC Videsh.
The 1/2/4 block in South Sudan, that produces mainly a medium sweet crude called Nile Blend, has entered its latter stage of production, while block 3/7 and block 5 produce largely heavy crude, the report said.
(READ MORE: South Sudan’s kiir to keep oil minister, change finance portfolio)
All of these fields require EOR technology to boost output.
The report did not give further details.
A South Sudanese oil official put production in late June at about 160,000 barrels per day. It had been in the range close to 260,000 bpd.