We have proposed mobile Personal Area Network (mPAN) that enables mobile devices user to exploit services from peripheral devices around the user. In the mPAN, the mobile devices and peripheral devices have to obtain an IP address, because we assume that they communicate with the Internet Protocol (IP). In this paper, we propose a protocol that assigns IP addresses to nodes in an mPAN dynamically. In an mPAN, communication between a mobile device and peripheral devices are limited within one hop. It is ideal for mobile devices like cellular phones to consume less power to use mPANs. Then, we propose a dynamic address assignment protocol specialized for one hop communication between a mobile device and peripheral devices, and that reduces power consumption of mobile devices. We implemented the prototype of the protocol and confirmed that it worked properly in wireless networks including hidden terminals.