MMMR: Benchmarking Massive Multi-Modal Reasoning Tasks
Authors: name: Guiyao Tie, name: Xueyang Zhou, name: Tianhe Gu, name: Ruihang Zhang, name: Chaoran Hu, name: Sizhe Zhang, name: Mengqu Sun, name: Yan Zhang, name: Pan Zhou, name: Lichao Sun

Recent advances in Multi-Modal Large Language Models (MLLMs) have enabled
unified processing of language, vision, and structured inputs, opening the door
to complex tasks such as logical deduction, spatial reasoning, and scientific
analysis. Despite their promise, the reasoning capabilities of MLLMs,
particularly those augmented with intermediate thinking traces (MLLMs-T),
remain poorly understood and lack standardized evaluation benchmarks. Existing
work focuses primarily on perception or final answer correctness, offering
limited insight into how models reason or fail across modalities. To address
this gap, we introduce the MMMR, a new benchmark designed to rigorously
evaluate multi-modal reasoning with explicit thinking. The MMMR comprises 1) a
high-difficulty dataset of 1,083 questions spanning six diverse reasoning types
with symbolic depth and multi-hop demands and 2) a modular Reasoning Trace
Evaluation Pipeline (RTEP) for assessing reasoning quality beyond accuracy
through metrics like relevance, consistency, and structured error annotations.
Empirical results show that MLLMs-T overall outperform non-thinking
counterparts, but even top models like Claude-3.7-Sonnet and Gemini-2.5 Pro
suffer from reasoning pathologies such as inconsistency and overthinking. This
benchmark reveals persistent gaps between accuracy and reasoning quality and
provides an actionable evaluation pipeline for future model development.
Overall, the MMMR offers a scalable foundation for evaluating, comparing, and
improving the next generation of multi-modal reasoning systems.