Road construction brings social and economical benefits,but meanwhile seriously destroys the structure and disturbs the functions of ecosystem.Thus it becomes a threat to ecosystem health.The ecological effects of road construction are analyzed in terms of the components,structure,and functions of ecosystem,which appears a cascade response process.The method used to analyze such ecological effects is mechanism discussing.The variability of ecosystem structure in space and time scales under the disturbance of road construction is discussed,such as the changes of hydrology pattern,vegetation succession,and wildlife distributing structures.Road construction also disturbs the continuity of the process of ecosystem cycle,energy flow,and information transmission.Ecological measures to mitigate the ecological effects during the programming,constructing,and running period are raised,which involve ecological programming,ecological restoration,and ecological compensating.The ecological theories and methods are used to guide the construction of roads in order to find a way of harmony development among social,economic,and ecological benefits and eventually achieve sustainable development.