Abstract:A new theory based on uncertainty was introduced into the inspection and overhauling of monolithic track-bed.In order to minimize the expenses in remaining life,the theory is used to seek optimal interval for inspection and critical value for overhauling with recursion method. Finally,a model was established by using MATLAB and an example was computed to study the relationship between deterioration level and optimal interval.So the key problems of inspection and overhauling of monolithic track-bed were solved on arithmetic aspect.