VisualPRM: An Effective Process Reward Model for Multimodal Reasoning
Weiyun Wang, Zhangwei Gao, Lianjie Chen, Zhe Chen, Jinguo Zhu, Xiangyu Zhao, Yangzhou Liu, Yue Cao, Shenglong Ye, Xizhou Zhu, Lewei Lu, Haodong Duan, Yu Qiao, Jifeng Dai, Wenhai Wang
2025-03-14

Summary
This paper talks about VisualPRM, a smart AI tool that helps image-and-text AI models think step-by-step like humans, checking each part of their reasoning to avoid mistakes.
What's the problem?
Current AI models that handle images and text together often make errors in their reasoning steps, leading to wrong answers even if the final result looks okay.
What's the solution?
VisualPRM acts like a step-by-step coach for these AI models, using a huge dataset of labeled examples to spot and fix mistakes in their logic before they reach the final answer.
Why it matters?
This makes AI systems more reliable for tasks like answering questions about photos or explaining diagrams, helping students, researchers, and professionals get accurate results faster.
Abstract
We introduce VisualPRM, an advanced multimodal Process Reward Model (PRM) with 8B parameters, which improves the reasoning abilities of existing Multimodal Large Language Models (MLLMs) across different model scales and families with Best-of-N (BoN) evaluation strategies. Specifically, our model improves the reasoning performance of three types of MLLMs and four different model scales. Even when applied to the highly capable InternVL2.5-78B, it achieves a 5.9-point improvement across seven multimodal reasoning benchmarks. Experimental results show that our model exhibits superior performance compared to Outcome Reward Models and Self-Consistency during BoN evaluation. To facilitate the training of multimodal PRMs, we construct a multimodal process supervision dataset VisualPRM400K using an automated data pipeline. For the evaluation of multimodal PRMs, we propose VisualProcessBench, a benchmark with human-annotated step-wise correctness labels, to measure the abilities of PRMs to detect erroneous steps in multimodal reasoning tasks. We hope that our work can inspire more future research and contribute to the development of MLLMs. Our model, data, and benchmark are released in https://internvl.github.io/blog/2025-03-13-VisualPRM/.