Nowadays many applications in precision engineering would be impossible without a careful isolation of the instrument from the vibration sources. To reduce the vibration on precision instruments, active isolation systems are urgently required, since these units can achieve a very low remaining vibration level. This paper is concerned with the development of a vibration isolation system for highly sensitive equipment applications. In this paper, a 3-DOF parallel robot with flexure hinges will be analyzed and a dynamic model will be presented intended to facilitate the design of an optimal controller. The chosen approach is the method of Thomas R and the analysis result is a state-space, analytical set of linearized equations of motion. The investigations of this paper may not only have significance in robotics research, but also make contributions to the research on active vibration isolation based on parallel manipulators. © 2008 SICE.