Artificial intelligence analysis methods for chest X-ray images are limited by insufficient annotation data and varying levels of annotation, resulting in weak generalization ability and difficulty in clinical dissemination. Here, we present EVA-X, an innovative foundational model based on X-ray images with broad applicability. EVA-X uses a self-supervised learning method capable of capturing both semantic and geometric information from unlabeled images for universal X-ray image representation. It has demonstrated exceptional performance in chest disease analysis and localization, becoming a model capable of spanning over 20 different chest pathologies and achieving leading results in over 11 different pathology detection tasks. Additionally, EVA-X significantly reduces the burden of data annotation in the medical AI field, showcasing strong potential in the domain of few-shot learning. The emergence of EVA-X will greatly propel the development and application of foundational medical models, leading to potential improvements in future medical research and clinical practice.