As an important method to synthesize new materials and a clean way to adjust the lattice constants,pressure has known to be a powerful tool to study the physical properties of materials.Recently,high pressure studies of quantum materials become popular because pressure is an effective way to probe the interplay between lattice and the exotic properties of quantum materials,such as topological edge states,Weyl fermions,unsaturated magnetoresistance and superconductivity,etc.I will present several of our recent work,which show close collaborations between ab initio calculations and experiments are essential to design functional materials and understand the phenomena of quantum materials under high pressure.