Recently, above 60% of the trade deficit between Korea and Japan originate from the parts and materials industries. Causes of the trade deficit in parts and materials between Korea and Japan are the import induction by industrial structure, the price of raw materials, the fall of the exchange rate in won and yen, the price competitiveness decline. And existing researchers consider just the cause of the trade deficit increase between Korea and Japan. In this study, we design the causal-effects model including the various cause of increase of the parts and materials import with Japan. analyze the direct factors influencing on the parts and materials increase in import with Japan are the world export amount and the domestic parts and materials turnout, the parts and materials unit cost of import, and the parts and materials technology competitiveness. Also, we quarterly predict the indirect factors by the business trends, the exchange rate of won and dollars, oil price, value added.