The “arrow cost accounting” proposed in this application is constructed so that an accounting system for job costing can be applied to more general production data. Based on collected production data and cost data, a cost accounting result precisely corresponding to a procedure of a processing work is obtained. A product manufacturing cost accounting program causes a computer to perform product manufacturing cost accounting. The computer is caused to: refer to: 1) cost accounting space data defined by a coordinate space comprising a degree of processing progress axis; 2) processing work introduction amount function data as an introduction condition for the processing work; 3) present term production data as a production situation within a cost accounting target period; and 4) present term actual cost data as a cost generation situation within the given cost accounting target period stored in a memory; read the cost accounting space data and the present term production data; perform a step of calculating an arrow that connects an input node and an output node based on an inputted matching and a material amount on an arrow path as a material amount on a path of the arrow; read the processing work introduction amount function data and material amount data on the arrow path to calculate a processing work conversion amount and a material introduction conversion amount if a solution matching is found in the step of calculating the material amount on the arrow path; and perform a step of reading the present term actual cost data, the processing work conversion amount, and the material introduction conversion amount, distributing costs to the arrows, and outputting the costs distributed to the arrows.