Apple's share of the Chinese smartphone market fell last quarter, according to one analysis, representing the waning dominance of the iPhone ahead of a major milestone.

Local brand Xiaomi snagged the fourth-place spot that was held by Apple, leaving Apple at No. 5, according to Canalys, an independent analyst company. Samsung is also in the top 10 smartphone brands in China, although only the top four brands were ranked by Canalys' statement.

• Huawei: 23 million

• Oppo: 21 million

• Vivo: 16 million

• Xiaomi: 15 million

• Source: Canalys

Apple does not break out figures on sales of individual products in each region, and was not immediately available to comment. But earlier this year, a separate report from Counterpoint Research found that the iPhone was not the top selling smartphone in China in 2016, the first time Apple had been unseated since 2012.

Remaining in the top of the crop is key for Apple because the top five brands accounted for almost 75 percent of the 113 million shipments in China, Canalys estimates. It's an area where Apple has struggled in recent years, with sales down 14 percent year over year last quarter.

Apple CEO Tim Cook has expressed long-term optimism on the Chinese market, despite strong competition provided by WeChat's software ecosystem, which works on Android or iPhone devices. Apple recently created a new post, managing director of greater China, tapping an executive that has developed China-specific features for iPhone and iPad.

The iPhone 8, considered a marker of the device's tenth anniversary, is expected by some analysts to revamp Apple's influence in China. Sales in greater China are expected to hit $9.96 billion in the September quarter, according to FactSet, up from $8.79 billion in the year-ago quarter.

Source: CNBC