Journal Article
Knowledge Graphs

Graph Retrieval-Augmented Generation: A Survey

Boci Peng(Peking University), Yun Zhu(Zhejiang University), Yongchao Liu(Ant Group (China)), Xiaohe Bo(Renmin University of China), Haizhou Shi(Rutgers, The State University of New Jersey), Chuntao Hong(Ant Group (China)), Yan Zhang(Peking University), Siliang Tang(Zhejiang University)
November 19, 2025ACM Transactions on Information Systems672 citations

672

Citations

33

Influential Citations

ACM Transactions on Information Systems

Venue

2025

Year

Abstract

Recently, Retrieval-Augmented Generation (RAG) has achieved remarkable success in addressing the challenges of Large Language Models (LLMs) without necessitating retraining. By referencing an external knowledge base, RAG refines LLM outputs, effectively mitigating issues such as “hallucination,” lack of domain-specific knowledge, and outdated information. However, the complex structure of relationships among different entities in databases presents challenges for RAG systems. In response, GraphRAG leverages structural information across entities to enable more precise and comprehensive retrieval, capturing relational knowledge and facilitating more accurate, context-aware responses. Given the novelty and potential of GraphRAG, a systematic review of current technologies is imperative. This article provides the first comprehensive overview of GraphRAG methodologies. We formalize the GraphRAG workflow, encompassing Graph-Based Indexing, Graph-Guided Retrieval, and Graph-Enhanced Generation. We then outline the core technologies and training methods at each stage. Additionally, we examine downstream tasks, application domains, evaluation methodologies, and industrial use cases of GraphRAG. Finally, we explore future research directions to inspire further inquiries and advance progress in the field. In order to track recent progress, we set up a repository at https://github.com/pengboci/GraphRAG-Survey .

Analysis

Why This Paper Matters

Retrieval-Augmented Generation (RAG) has become a cornerstone technique for enhancing Large Language Models (LLMs) by grounding their outputs in external knowledge, thereby reducing hallucinations and injecting up-to-date or domain-specific information. However, traditional RAG systems often treat knowledge as flat text chunks, overlooking the rich relational structure inherent in many databases. Graph Retrieval-Augmented Generation (GraphRAG) addresses this gap by leveraging graph structures to capture entity relationships, enabling more precise and context-aware retrieval. As the first comprehensive survey of GraphRAG, this paper arrives at a critical juncture when the field is rapidly expanding but lacks a unified framework for understanding and comparing methods.

The survey's significance is further amplified by its timing: GraphRAG has seen a surge of interest from both academia and industry, yet the literature remains fragmented. By formalizing the GraphRAG workflow into three coherent stages—Graph-Based Indexing, Graph-Guided Retrieval, and Graph-Enhanced Generation—the authors provide a structured lens through which to evaluate existing approaches and identify gaps. This framework not only aids newcomers in navigating the landscape but also serves as a common vocabulary for researchers to position their contributions.

Moreover, the paper goes beyond mere taxonomy by examining downstream tasks, application domains, evaluation methodologies, and industrial use cases. This holistic view bridges the gap between theoretical research and practical deployment, making it valuable for practitioners seeking to implement GraphRAG in real-world systems. The accompanying GitHub repository ensures that the survey remains a living resource, tracking the latest developments in this fast-moving area.

Technical Contributions

  • Unified Workflow Formalization: The survey introduces a three-stage framework (indexing, retrieval, generation) that decomposes GraphRAG into modular components, enabling systematic comparison and analysis of existing methods.
  • Comprehensive Technology Review: It outlines core techniques at each stage, including graph construction, representation learning, retrieval algorithms, and generation strategies, along with training methods such as joint optimization and fine-tuning.
  • Application and Evaluation Landscape: The paper catalogs downstream tasks (e.g., question answering, recommendation), application domains (e.g., healthcare, finance), and evaluation metrics, providing a practical guide for benchmarking GraphRAG systems.
  • Industrial Use Cases: It highlights real-world deployments, offering insights into scalability, efficiency, and integration challenges.
  • Future Directions: The authors identify open problems and promising research avenues, such as dynamic graph updates, multi-modal graphs, and interpretability.

Results

As a survey paper, it does not present original experimental results. Instead, it synthesizes findings from the literature, reporting on the performance gains of GraphRAG over traditional RAG in various studies. For instance, the paper discusses how graph-based retrieval improves accuracy in complex question answering by capturing multi-hop relationships, and how graph-enhanced generation reduces hallucinations by grounding responses in structured knowledge. The survey also notes that GraphRAG methods often outperform flat RAG baselines on tasks requiring relational reasoning, though direct comparisons are challenging due to varying experimental setups. The authors emphasize the need for standardized benchmarks and evaluation protocols.

Significance

This survey is poised to become a foundational reference for the GraphRAG community. By providing a clear taxonomy and identifying key challenges, it will guide future research toward more robust, efficient, and interpretable GraphRAG systems. The emphasis on industrial use cases and evaluation methodologies will help bridge the gap between research and practice, accelerating the adoption of GraphRAG in domains where relational knowledge is critical, such as healthcare, finance, and legal domains. Ultimately, this work contributes to the broader goal of making LLMs more reliable and knowledgeable by seamlessly integrating structured knowledge graphs.