Sonangol Sinopec International Limited (SSI) is a Chinese-Angolan petroleum company created in 2004 that is part of the Hong Kong-based 88 Queensway group. It is engaged in the oil and gas operations in Angola through the ownership of various oil blocks.

SSI was created in September 2004 as a joint venture between Cayman Islands registered Sinopec Group subsidiary Sinopec Overseas Oil & Gas Limited (SOOGL), China Sonangol International Holding Limited (CSIH), and Dayuan International Development Limited. CSIH had been founded only a month earlier and possessed no assets of its own, while Dayuan changed its name from Beiya later that year and both CSIH and Dayuan were 88 Queensway group companies. SOOGL owned a controlling 55% stake, with Dayuan and CSIH as minority partners with 31.5% and 13.5%, respectively.

Despite being pushed for primarily by Sonangol under CEO Manuel Vicente, this arrangement left Sonangol, and therefore the state of Angola, with only 4.05% ownership of SSI through its 30% stake in CSIH; the rest was split between the Chinese state, Chinese businessman Wu Yang, and New Bright International Development. The last of these was owned by Lo Fong Hung and by Veronica Fung Yuen Kwan, the wife of Sam Pa, a Chinese-born citizen of Angola living in Hong Kong whose connections in China and Angola are believed to have helped lubricate SSI's early deals. Hung is director of SSI (and of dozens of other Queensway companies), while her husband Wang Xiangfei is chief financial officer. Yang and Pa have apparent ties with both the Chinese intelligence apparatus and with the Angolan government, including Sonangol's executive leadership.

They got the loan, we paid Shell […] It was, let's say, 800-something [million dollars]. And after that, later on…we called Sinopec.

— Manuel Vicente

In 2006, SSI was selected by Sonangol to participate in funding the construction of an oil refinery in the port city of Lobito. The Lobito Oil Refinery was expected to have a total cost of US$ 3 billion, employ 8,000 people, and have a capacity of 240,000 barrels per day. However, an agreement was never ultimately reached between Sinopec and the Angolan government. Sinopec's plan called for 80% of the output to go to foreign markets despite Angola regularly suffering its own shortages of refined petroleum products. Manuel Vicente told Angolan media, "We cannot construct a refinery just to make products for China," while Chang Hexi, the Chinese economic counselor in Angola, stated the company was simply disinterested in the project. SSI was ultimately uninvolved in the refinery's construction, which would ultimately not begin until 2015, and would then be paused due to lack of funding until 2021.

SSI vice president Francisco Gonçalves was among the Angolan businessmen and government officials implicated through the Panama Papers in 2016. Leaked emails reveal him taking bribes from Monaco-based consultancy firm Unaoil, described as a "corruption factory", totalling about US$3.5 million as part of a scheme to gain Swiss equipment supplier Sulzer favorable deals with SSI's parent company, Sonangol."

We need to be able to bring FG on board as he appears to be involved in a big part of the business.