In real complex systems,the limited storage capacity of physical devices often results in the loss of data.We study the effect of buffer size on packet loss threshold in scale-free networks.A new order parameter is proposed to characterize the packet loss threshold.Our results show that the packet loss threshold can be optimized with a relative small buffer size.Meanwhile,a large buffer size will increase the travel time.Furthermore,we propose a Buffered-Shortest-Path-First (BSPF) queuing strategy.Compared to the traditional First-In-First-Out (FIFO) strategy,BSPF can not only increase the packet loss threshold but can also significantly decrease the travel length and travel time in both identical and heterogeneous node capacity cases.Our study will help to improve the traffic performance in finite buffer networks.