The CFO position has been empty since last November, when Shou Zi Chew, the current head of TikTok, stepped aside to focus on his position as chief executive officer at the short-video platform.

Ms. Gao’s hiring comes as the Chinese technology company faces an impasse in its quest for an IPO. The Beijing-based company indefinitely put on hold its intentions to list offshore early last year after government officials told the company to focus on addressing data-security risks, the Journal reported in July.

ByteDance, one of the world’s most valuable technology startups, counts

Carlyle Group Inc.

and Sequoia Capital among its investors.

This month, ByteDance started a round of stock option buybacks from employees at $142 per share, a 7.6% increase from an earlier buyback last October, people familiar with the matter said. The company also allowed top-performing staff to turn their annual bonus into options at the same rate.

Current employees said they were reluctant to exchange their bonus for stock options, as the company had shelved their IPO plan, and they were worried the weaker market environment might weigh on any possible IPO performance.

Born in Shanghai, Ms. Gao studied law as an undergraduate at China’s Peking University, after her father strongly encouraged her to do so, believing it would be a useful major, she told the Journal in an interview in 2019. At college, she was a reporter for the school newspaper and practiced hard-tipped brush pen Chinese calligraphy.

According to her profile page on the law firm’s website, Ms. Gao has advised on the initial share sale and other capital market activities of large technology companies including Meituan, and

JD.com Inc.

while at Skadden.

She provided advice to ByteDance when the company sought to acquire Musical.ly and gaming company Shanghai Moonton Technology Co., and helped the Chinese tech company navigate several rounds of private-equity financing.

In the letter to ByteDance staff from CEO Liang Rubo, Mr. Liang said Ms. Gao has had a working relationship with the company since 2016, adding that “she is familiar with our mission, culture, teams and business.”

Ms. Gao, who would be working out of the company’s Hong Kong and Singapore offices, will likely start in her new role in the next few weeks, according to a person familiar with the matter.

Mr. Chew, a former CFO at Xiaomi Corp., was initially tapped for the CFO role at ByteDance last March, before adding his role as TikTok CEO about two months later. By November, the company reported he had stepped down from his role as ByteDance’s CFO.

—Raffaele Huang contributed to this article.

Write to Liza Lin at Liza.Lin@wsj.com