Abstract:A nonlocal model for heat conduction problems of orthotropic plates is developed by using peridynamic differential operator (PDDO). The boundary conditions and heat conduction equations are transformed from local differential form to nonlocal integral form by introducing the peridynamic function. Lagrange multipliers and variational analysis were introduced to solve the temperature and heat flux distributions at the crack tip of orthotropic plates. The convergence and effectiveness of the proposed model are verified by the comparative examples. The effects of orthotropy, material ply angle, crack angle and spacing on heat flux at crack tip were analyzed. The results show that the heat conduction model of orthotropic plate based on PDDO can effectively improve the calculation accuracy and predict the singularity of crack tip.