Abstract: Spatial arrangement is a key factor for layout optimization of fire protection facilities.The path analysis based on the proposed space-time allocation model provides a solid measure for the layout optimization. It is often simplified by using a circular area based on the facility location to represent a buffer zone or simply consider only the road segments that a fire engine has to travel.In this research,we introduce a hybrid measurement considering both travel time on the main roads and the inner part of a neighborhood for layout optimization of fire protection facilities.Furthermore,some indices are introduced to measure the service level of spatial arrangement of fire protection facilities quantitatively.Finally,some testing results are produced and presented by using modeling techniques in ArcGIS software and they show that the proposed approach is much more appropriate than the two simplified versions.