In order to study the characteristics and calculation method of interior ballistic with the low temperature sensitivity coated propellant charge, the parameters at the potential equilibrium point with standard charge and the low temperature sensitivity coated propellant charge were compared by the potential equilibrium theory. The reason why ψ_E (the relative amount of burned propellant) at the potential equilibrium point changed with the charge density was analyzed and the actual burning gas formation function was fitted. The simulation of the interior ballistic was carried out based on the above. The results show that the calculated curve is in good agreement with the experimental curve and the potential equilibrium theory can be used to study the combustion laws of the low temperature sensitivity coated propellant charge.