Coal is a porous medium with complex pore structures. Nanopore structure in coal particle is the basic underlying factor driving coal particle strength. A better knowledge of nanopore structure – coal particle strength correlation is of great significance for coal mining and other fields of engineering problems. In this study, for the first time, we conducted an in-situ nanoscale characterization of structure and mechanical properties of coal particle using synchrotron radiation nano-CT. Furthermore, a parametric study of the nanopore structure – coal strength correlation was performed using numerical simulation, which is on the basis of manually-generated pore structure with predefined pore size distribution (PSD) and anisotropy value, and accurate PSD parameters. The nanoscale PSD in coal follows lognormal distribution. Improved quartet structure generation set (QSGS) method was developed to generate pore structure with predefined PSD and anisotropy value. The impact of porosity and pore structure anisotropy on coal particle strength was quantitatively investigated.