This chapter deals with Matrix structural analysis and its applications to the stiffness modelling of robotic manipulators. It starts from general assumptions and definitions and comes to describing the stiffness model of parallel robots based on this technique. The Chapter describes in detail the required matrix transformations that allow the user to obtain the desired force-deflection relation and torque/deflections in internal mechanical elements. The particularities of this method and its application are illustrated by an application example that deals with the stiffness analysis of the NAVARO parallel manipulator.