The next-generation technology for electronics is wearable and flexible electronics system. This electronics system should be sustaining large deformations geometrically without caused failure in the materials and microstructures, which it is constructed. There are wide applications of wearable and flexible electronics system such as communicative packaging, flexible sensors, medical devices and soft robotic, which required flexibility and conformability at system level. Computation simulation, which is based on the computational solid mechanics studies, is an powerful tools to understanding and aided design of these systems. The modelling and simulation can used to found the max. stress and strain in the system under the usage conditions and to provide and establish design criteria. It is important for the design the electronics device without defect and failure. Furthermore, the numerical simulation are useful to optimize mechanics and materials in the design of electronic circuits with maximum stretchability. In this study, numerical modelling and simulations are used to investigate the mechanics performance of materials and structural system for this type of electronics devices, which have excellent bendability and stretchability. The high flexibility makes them very useful and advantage for wearable devices. This type designs are possible to fabricate the high performance electronics system with bendable, and stretchable with strains of near to 100% or more. It is a potential way to make high performance silicon semiconductor. To do so, the significant high stress or strain could be avoided during the application with, folding, bending, twining and other type of deformation. Computational modelling are important tools to study the basic features of the behaviour of flexible and wearable electronic systems from mechanics aspects.