In this letter we introduce a novel change detection approach called ChangeGAN for coarsely registered point clouds in complex street-level urban environment. Our generative adversarial network-like (GAN) architecture compounds Siamese-style feature extraction, U-net-like use of multiscale features, and Spatial Trans-formation Network (STN) blocks for optimal transformation estimation. The input point clouds are represented by range images, which enables the use of 2D convolutional neural networks. The result is a pair of binary masks showing the change regions on each input range image, which can be backprojected to the input point clouds without loss of information. We have evaluated the proposed method on various challenging scenarios and we have shown its superiority against state-of-the-art change detection methods.