A new method integration of "3S" (geographic information system (GIS), global positioning system (GPS), remote sensing(RS)) for mobile landscaping survey and update is studied in mobile GIS. Several Key technologies are presented in the method, including spatial data model on mobile personal digital assistant (PDA), GPS data difference processing and representation in GIS, GPS coordinate transformation model in mobile GIS, the method of PDA integration of Total Station, the RS image process based on Mobile Device. A new object-oriented spatial data model based on mobile GIS is proposed that has high query and display efficient. A new least squares-based GPS transformation model is further proposed that has fast calculation speed, high adjustment accuracy and thus suitable for mobile GIS. An integrative Application system integration of "3S" for landscaping survey, update and management is therefore developed, including spatial data survey and update mobile GIS, spatial data processing and maintain desktop GIS and spatial data publication WEBGIS. A field test is carried out through this system in Shanghai, and the results show that the proposed model and methods are feasible for mobile landscaping information survey, update and gridding management.