A photo of Yu Huaying at the Intermediate People's Court of Guiyang in Guiyang province, China, on Oct 25, 2024. China on Dec 19, 2024, upheld Yu's death sentence for trafficking children. (File photo: WeChat/The Intermediate People's Court of Guiyang)
Yu Huaying, 60, separated at least 17 children from their parents and sold them to other families during the 1990s.
She was first handed the death penalty last year but appealed her sentence, a move that commonly results in clemency in China.
But state media reported Thursday that a court in southwestern Guizhou province had rejected her appeal and upheld capital punishment.
"This ruling is final, and Yu Huaying cannot appeal again," state broadcaster CCTV reported.
"The case will now be submitted to the Supreme People's Court for review... and then will enter the implementation stage," CCTV said.
Human trafficking is a significant issue in China, and some cases have provoked a widespread public outcry once exposed.
In recent years, child kidnappings have featured more prominently in popular culture, and state media gave Yu's case extensive coverage.
Her crimes became widely known in 2022 when a woman whom she sold for less than $350 in 1995 reported her experience to police.
Now in her 30s, Yang Niuhua documented her search for her birth family on social media, but found her biological parents had already died.
Yu was detained the same year and initially handed a death sentence in September 2023 for trafficking 11 children.
During her appeal, the court discovered enough additional evidence to convict her of trafficking a further six.
Yu generally abducted them in southwestern China and sold them through intermediaries to families hundreds of kilometres (miles) further north.
State media reported in October that the first child she sold was her own son while in "financial difficulties" decades ago.
Many of Yu's victims experienced depression and some families later split up under the emotional strain, according to state media.
China classifies death penalty statistics as a state secret, though rights groups believe thousands of people are executed there every year.
Several high-profile human trafficking cases have emerged in China in recent years.
A court jailed six people in 2023 for trafficking a woman found chained in a dirt-floor hut in eastern Jiangsu province.
For decades under the one-child policy, a cultural preference for boys led many Chinese families to sell or abandon unwanted baby girls.
China began allowing all families to have two children in 2016 and three children from 2021.