In the last few years,charge order and its entanglement with superconductivity are under hot debate in high-Tc community due to the new progress on charge order in high-Tc cuprate superconductors YBa2Cu3O6+x.Here,we will briefly introduce the experimental status of this field and mainly focus on the experimental progress of high-field nuclear magnetic resonance (NMR) study on charge order in YBa2Cu3O6+x.The pioneering high-field NMR work in YBa2Cu3O6+x sets a new stage for studying charge order which has become a ubiquitous phenomenon in high-Tc cuprate superconductors.