The Google Maps JavaScript API technology is described briefly, with the emphasis on the monitoring webpage design for ship automatic weather stations by using the mainstream WebGIS technology. The AJAX technology is used to solve the key problem that large amounts of meteorological data are requested by the webpage from remote data server, and the returned data, which are JOSN data format, are loaded into the Google Maps. The custommade ship icons and track icons are rendered into the monitoring webpage visually by using the Google Maps JavaScript. This technique has been applied to the devices monitoring system of the Guangdong Provincial Meteorological Service successfully.