Mobile ad hoc networks (MANETs) are spontaneously formed with a set of wireless nodes without any existing infrastructure or administrative support. The intrinsic characteristics of these networks such as the dynamic topology and the scarcity of resources mainly bandwidth and nodes battery life make network management process a challenging task. In this paper, we present the design and a performance evaluation of a distributed policy management system that aims to enable self-QoS-management of MANETs. The key idea is to extend policy decision point (PDP) functionalities to every mobile ad hoc node in order to support self-configuration and self-adaptation capabilities. We propose the management of the MANET in a fully distributed manner using a new named DPMP for Distributed Policy Management Protocol. First, we present our decentralized framework. Then, we evaluate the proposed policy distribution mechanism through simulations. Results show that the protocol incurs low latency and message overhead for policies distribution while varying node mobility, network size and density.