Abstract: In mesh free methods, discrete equations are built according to physics information of micro-bodies arbitrarily spread in vicinal space. As requirements about topology of micro-bodies are reduced, simulations with Lagrangian approach may be easier even with large distortions. Owing to insufficiency of topological information, there is a challenge for mesh-free method to reflect physics especially as discontinuities exist. In this paper a new mesh free systematic method PECM (Physics Evoked Cloud Method) based on physical laws and developing trend of numerical simulation is shown, which has excellent applicability. High fidelity to physics of the method is demonstrated through several 1-dimentional problems in which strong discontinuities exist.