ACL2026

EvoMemKG: An Evolvable Memory Agent for Multi-hop Knowledge Graph Reasoning

Shiyu Tian, Shuyue Xing, Zhuoxin Han, Caixia Yuan, Xiaojie Wang

Abstract

Integrating knowledge graphs (KGs) with large language models (LLMs) enhances factual accuracy and interpretability in question answering (QA). However, existing agent-based methods rely on static memory mechanisms, which fail to address the state-space explosion in multi-hop reasoning and lack self-evolution capabilities. To overcome these limitations, we propose EvoMemKG, an agent framework with an evolvable memory mechanism for multi-hop KG reasoning. EvoMemKG introduces a dual-layer memory: (1) a working memory that manages and compresses intermediate states using a relation-based compression algorithm, effectively reducing context usage; and (2) an experience memory that distills historical reasoning paths into reusable, generalized strategies, enabling cross-task knowledge transfer and self-evolution. We further design a double-loop workflow that orchestrates the LLM, the dual-layer memory, and KG environment to enable end-to-end autonomous reasoning. Extensive evaluations on three KGQA datasets across two KGs demonstrate that EvoMemKG achieves state-of-the-art performance without requiring additional training or specialized tools, with improvements of up to 20% over strong baselines on complex multihop queries.