Wireless power transfer (WPT) is one of the most promising technologies opening the huge market currently in mobile devices and electric vehicles, and it expends the future applications to biomedical implants, wearable devices, IoT sensors, and so on. The WPT technology provides convenience and safety with its wireless connection, however, it is true that our electromagnetic environment is threatened by the unwanted electromagnetic field from the WPT system, and the concerns on the electromagnetic interference to other electronic devices or human bodies are consequently increasing. This talk covers the electromagnetic issues related with the electromagnetic compatibility and harmful electromagnetic field of WPT technology.