Abstract
This paper attempts to investigate the purpose of cost accounting used for determining the price in war time military production, the difference in Imperial Japanese Army （IJA） and Imperial Japanese Navy（ IJN） and the succession after WW2 from the relationship with Board of Audit.
IJN used cost accounting to improve production efficiency and reduce cost，and contract officers also determined contract price based on contractor’s cost reports. On the other hand, IJA used cost accounting to estimate contract price. IJA determined the proper price based on estimated cost and profit. The difference of production quantity in transition into wartime made those differences.
After WW2, MoD selected proper price principle which was used in IJA. As profit is calculated on regulated formula, basically results are almost identical. Therefore cost auditor approved IJA method was easy from the view of validity and cost efficiency.
