Low-resource event extraction presents a significant challenge in real-world applications, particularly in domains like pharmaceuticals, military and law, where data is frequently insufficient. Data augmentation, as a direct method for expanding samples, is considered an effective solution. However, existing data augmentation methods often suffers from text fluency issues and label hallucination. To address these challenges, we propose a framework called Agent-DA, which leverages multi-agent collaboration for event extraction data augmentation. Specifically, Agent-DA follows a three-step process: data generation by the large language model, collaborative filtering by both the large language model and small language model to discriminate easy samples, and the use of an adjudicator to identify hard samples. Through iterative and selective augmentation, our method significantly enhances both the quantity and quality of event samples, improving text fluency and label consistency. Extensive experiments on the ACE2005-EN and ACE2005-EN+ datasets demonstrate the effectiveness of Agent-DA, with F1-score improvements ranging from 0.15% to 16.18% in trigger classification and from 2.2% to 15.67% in argument classification. The code and models can be found at https://github.com/GYK-CASIC/Agent-DA.