Wireless mesh networks (WMNs) are promising last-mile access network with large coverage and low deployment and operational cost. As the realization of WMNs becomes attainable, business opportunities have focused a number of applications such as multimedia streaming. However, in the case of multiple clients streaming, intrinsic nature of wireless medium sharing property results severe streaming bandwidth unfairness among the clients. To cope with this problem, this paper proposes an effective and practical distributed solution for fair bandwidth allocation among streaming clients in IEEE 802.11-based WMNs based on proportionally normalized congestion price. Especially, we approximate the congestion price from the intermediate streaming flow rate, and finally coordinate the resulting WMNs by taking the proportional normalization to the congestion price. As validation, ns-2 simulations are conducted and the results show that, under heavily congested streaming scenario, the proportional fairness is improved almost two times compared to the original IEEE 802.11 WMN.