Unicom has been stepping up efforts to push forward a structural reform to introduce mixed ownership, something that triggered speculation about possible private sector investors.
Reuters news agency reported on Thursday that Alibaba and Tencent will likely partner others to invest $10 billion in the listed Shanghai unit of Beijing-based Unicom.
But, in a statement on Friday, Unicom refuted the report.
Unicom is among the first batch of State-owned enterprises or SOEs that have been shortlisted for mixed ownership.
Unicom had indicated there may be changes in the shareholding pattern of its listed Shanghai subsidiary, China United Network Communications Ltd.
Unicom is already collaborating extensively with internet heavyweights such as Alibaba, Tencent and Baidu Inc in telecom services, information infrastructure and other emerging businesses.
Xiang Ligang, a telecom expert and CEO of the telecom industry website cctime.com, said that Unicom's clarification on Friday notwithstanding, it is still possible that the net giants may yet invest in it. It is also possible the investment figures cited in the Reuters report may not be accurate, he said.
"An access to the basic telecom infrastructure resources, such as servers and bandwidth, can greatly help Tencent and Alibaba's cloud computing and other businesses."
But it would not be possible for them to have a big stake in Unicom, given that telecommunications has high national strategic importance, he said.
Last October, Tencent and China Unicom jointly launched low-cost data traffic packs, which attracted 20 million users within half a year.
Unicom is locked in a stiff competition for market share with China Mobile Communications Corp and China Telecommunications Corp.
Wang Xiaochu, chairman of Unicom, said in May that the company was talking with 10 ministries to accelerate the reform process. As part of mixed ownership, Unicom may give key employees stock options.