The environmental monitoring data of air-quality, acid rain, water and city noise is the mainly information of environmental monitoring. Based on WebGIS platform, to collect the public data and manage them reasonably can greatly support the environmental information publicity. In this paper, the system is based on B/S structure, and developed under PHP combining with MapServer platform and JavaScript library for GIS. MapServer is an Open Source platform for publishing spatial data and interactive mapping applications to the web. Some JavaScript library for GIS can greatly support the interaction in WebGIS. The back-end database is adopted PostGIS to store and manage. All GIS and web framework in this system is based on MapServer and other open source GIS software.