This project presents the design and implementation of a web service for LiteOS-based wireless sensor networks (WSNs) to remotely monitor the light, temperature, magnet, and acceleration of the physical world. LiteOS is a newly developed operating system for the sensor motes. Taking advantage of UNIX-like shell commands and C programming language supported by LiteOS, this proposed web service enables the users to remotely query and visualize the sensor readings. Web service system is equipped with secure membership, a visualizer for sensor readings, and accepts parameterized queries.