Infant Incubator is the most important equipment in a infant ICU. This maintain adequate temperature and humidity for survival of infants. The final object of this research is Web-based monitoring of several infant incubators in ICU. To realize these objects, we developed a temperature/humidity sensing module which is interfaced to Web server board via RS485 port. We used a small micro controller in each sensing module. So the size of this module is small enough to be attached to incubator. We can access each sensing module with RS485 port on Web server board via network. As a first trial, we networked 4 infant incubators. The operator can send alarms to each incubator and these alarms are indicated with sounds and lights on measurement module. Our system can increase the convenience by a intensive central monitoring, so instant handling to some kinds of accident is possible.