HopRAG: Multi-Hop Reasoning for Logic-Aware Retrieval-Augmented Generation

Hao Liu, Zhengren Wang, Xi Chen, Zhiyu Li, Feiyu Xiong, Qinhan Yu, Wentao Zhang


Abstract
Retrieval-Augmented Generation (RAG) systems often struggle with imperfect retrieval, as traditional retrievers focus on lexical or semantic similarity rather than logical relevance. To address this, we propose HopRAG, a novel RAG framework that augments retrieval with logical reasoning through graph-structured knowledge exploration. During indexing, HopRAG constructs a passage graph, with text chunks as vertices and logical connections established via LLM-generated pseudo-queries as edges. During retrieval, it employs a retrieve-reason-prune mechanism: starting with lexically or semantically similar passages, the system explores multi-hop neighbors guided by pseudo-queries and LLM reasoning to identify truly relevant ones. Experiments on multiple multi-hop benchmarks demonstrate that HopRAG’s retrieve-reason-prune mechanism can expand the retrieval scope based on logical connections and improve final answer quality.
Anthology ID:
2025.findings-acl.97
Volume:
Findings of the Association for Computational Linguistics: ACL 2025
Month:
July
Year:
2025
Address:
Vienna, Austria
Editors:
Wanxiang Che, Joyce Nabende, Ekaterina Shutova, Mohammad Taher Pilehvar
Venue:
Findings
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Publisher:
Association for Computational Linguistics
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Pages:
1897–1913
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URL:
https://preview.aclanthology.org/landing_page/2025.findings-acl.97/
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Cite (ACL):
Hao Liu, Zhengren Wang, Xi Chen, Zhiyu Li, Feiyu Xiong, Qinhan Yu, and Wentao Zhang. 2025. HopRAG: Multi-Hop Reasoning for Logic-Aware Retrieval-Augmented Generation. In Findings of the Association for Computational Linguistics: ACL 2025, pages 1897–1913, Vienna, Austria. Association for Computational Linguistics.
Cite (Informal):
HopRAG: Multi-Hop Reasoning for Logic-Aware Retrieval-Augmented Generation (Liu et al., Findings 2025)
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https://preview.aclanthology.org/landing_page/2025.findings-acl.97.pdf