Longyuan won the two South African projects in a tender in October 2013.
An engineering management firm Longyuan set up in South Africa is in charge of the projects as an EPC general contractor.
The De Aar phase 1 and 2 projects (100MW and 144MW respectively) will use 1.5MW turbines provided by Guodian United Power.
The two projects will be located in Northern Cape province and are being jointly developed by Longyuan, South Africa's Mulilo Renewable Energy and a local community company.
Construction work is expected to kick off in the second half of this year.
Longyuan Power and United Power are both affiliated with China Guodian Group, the fourth largest state-owned utility company in China.
Guodian has a number of subsidiaries engaged in renewable power development. By the end of 2014 Guodian's installed wind capacity totalled around 20GW, of which about 15.7GW is credited to Longyuan.
Statistics released by the China Wind Energy Association show United Power supplied 2.6GW of wind turbines to domestic developers in 2014, representing a market share of 11.14%.