• We proposed a new data augmentation method for few-shot medical diagnosis. • The proposed method can be used in different modality medical image data. • Extensive experiments are conducted to demonstrate the superior of the proposed method. In interactive remote medical diagnosis, medical diagnosis support system plays an important role in the pre-screening stage. Deep learning methods are widely used in such system especially medical imaging area to provide an initial diagnosis to support medical professional. However, the shortage of annotated medical images is one of the biggest challenges in the field of medical image computing. Without a sufficient number of training samples, deep learning based models are very likely to suffer from over-fitting problem. The common solution is image manipulation such as image rotation , cropping, or resizing. Those methods can help relieve the over-fitting problem as more training samples are introduced. However, they do not really introduce new images with additional information and may lead to data leakage as the test set may contain similar samples which appear in the training set. To address this challenge, we propose to generate diverse images with generative adversarial network . In this paper, we develop a novel generative method named generative adversarial U-Net, which utilizes both generative adversarial network and U-Net. Different from existing approaches, our newly designed model is domain-free and generalizable to various medical images. Extensive experiments are conducted over eight diverse datasets including computed tomography (CT) scan, pathology, X-ray, etc. The visualization and quantitative results demonstrate the efficacy and good generalization of the proposed method on generating a wide array of high-quality medical images.