The invention discloses a constructing method and a navigation method of a global boundary map. The constructing method comprises the following steps: firstly, determining a virtual cleaning zone in working space while a robot is started, labeling boundary characteristic information of a navigation boundary during a sweeping process of the virtual cleaning zone, and constructing a local boundary map; secondly, converting data of the local boundary map to a global coordinate system; moving to unswept zone after completing the sweeping of the virtual cleaning zone, determining a next virtual cleaning zone, continuously labeling the boundary characteristic information, repeatedly recycling, exiting the recycling after completing the sweeping of the whole working space, and completing construction of the global boundary map; finally, navigating by selecting the navigation boundary as a navigation path. According to the method for constructing the local boundary map and the global boundarymap, disclosed by the invention, rapid navigation of the robot is realized under a condition that the boundary characteristic information is reserved; meanwhile, system memory is saved, and the flexibility and high efficiency of navigation of the robot can be improved.