Title: Protecting DNN from Evasion Attacks using Ensemble of High Focal Diversity. Abstract: Edge AI continues to attract emerging applications that deploy well-trained DNN models on heterogeneous edge clients for real-time object detection. Recent studies have shown that evasion attacks on DNN object detection models at the test time are on the rise. Such evasion attacks generate deceptive queries using maliciously manipulated or out-of-distribution data, aiming to mislead high-quality object detectors during edge inference. This paper introduces ODEN, a novel approach to object detection ensemble, which combines a detection inconsistency solver with focal diversity-optimized ensemble pruning to defend against evasion attacks. The focal diversity ranking techniques enable ODEN to compose an ensemble from a pool of base object detectors with high failure independence, which strengthens the generalization performance of the ODEN ensemble in the presence of irregular query data and evasion attacks.  The ODEN inconsistency solver can detect and resolve three types of inconsistency by combining detection results from multiple DNN object detectors: the inconsistency of the object existence, the size and location inconsistency of the bounding boxes of detected objects, and the classification inconsistency of detected objects and their confidence. Extensive experiments on three benchmark vision datasets (OpenImages, COCO, and VOC) show that under no attack, ODEN can outperform existing ensemble methods by up to 9.33% of mAP. Compared to the low mAP of 2.64~18.07% under four evasion attacks, ODEN can maintain a high mAP of 58.97~86.00%, achieving up to an 82.44% increase in AI safety.