StepFun, a Shanghai company that builds large AI models, raised more than RMB 5bn (about $718m) in a Series B+ round, reported on 26 January 2026. TechNode described it as the largest single financing in China's large-model sector in the past 12 months. No lead investor and no valuation were disclosed.
The reports named new investors and existing shareholders but did not say who led. A Chinese-language report from 10jqka.com.cn carried the same figures.
Who invested
New investors were Shanghai SDIC Leading Fund, China Life Private Equity, Pudong Venture Capital, Xuhui Capital, Wuxi Liangxi Fund, Xiamen ITG Group and Huaqin Technology, plus other industrial investors, according to TechNode.
Existing shareholders Tencent Holdings, Qiming Venture Partners and 5Y Capital followed on.
What StepFun does
The Paper (Pengpai), a Chinese outlet, reported that StepFun was founded in April 2023 in Shanghai. Its management team comprises chief executive Jiang Daxin, a former Microsoft global vice president and natural language processing expert, chief scientist Zhang Xiangyu, a co-author of the ResNet image model, and Zhu Yibo, who leads systems and previously worked at Microsoft Research, ByteDance and Google Cloud.
10jqka.com.cn said the company has released language foundation models, multimodal models and device-cloud models, and is targeting automotive, phones and wearables, and embodied robots. The Paper reported three generations of foundation models so far, with Step 3 described as having industry-leading inference efficiency.
Chinese tech outlet iFanr said Jiang became the only IEEE Fellow from a Chinese large-model startup last year, and that Zhu has experience building clusters of ten thousand accelerators from scratch. It described StepFun's route as native multimodal training from interleaved image and text data, rather than bolting a vision encoder onto a language model.
A new chairman
On the same day, StepFun said Yin Qi would become chairman, responsible for the pace of company strategy and the direction of technology. The Paper reported that he previously led Megvii and has chaired Qianli Technology since 2024.
Neither report named StepFun's founders, and neither gave a headcount.
What the money is for
TechNode said the funding will advance foundation model development, build a major base model and accelerate StepFun's AI-plus-terminal strategy. The 10jqka report put it as building a top-tier global foundation model.
The Paper reported, citing internal sources, that about 60% of leading domestic phone brands have deep partnerships with StepFun, with more than 42 million installed model units and nearly 20 million daily users, and that the company expects its models to be in over one million vehicles this year. These are unverified claims relayed from the company.
iFanr reported that the round exceeds Moonshot AI's $500m Series C, and said StepFun's Step-GUI-Edge model, with 4 billion parameters, is claimed to outperform models with eight times as many parameters. It named OPPO, Honor and ZTE among phone partners.
Terminals
With Qianli and Geely, StepFun launched an AgentOS smart cockpit with an end-to-end voice model, the same Paper report said. The Geely Galaxy M9 sold nearly 40,000 units in its first three months. In December 2025 StepFun released what The Paper called an industry-first deployable GUI open-source model for phones, cars and PCs.
The sources reviewed do not list earlier funding rounds.