The aim of this research is to contribute to enhancing the competitiveness of automotive parts suppliers while departing from the dependent relationship structure, by developing and interpreting factors that affect sale, which are financial achievements, in a practical way. The research data covered 200 companies from 2013-2017. The study hypothesis was verified by dividing the hypothesis into Model1 with control variables only and Model2 with control variables in independent variables. As a result of hypothesis testing, regarding sales, only capital size showed to have an effect in Model1, while in Model2, asset size, number of employees and joint ventures with foreign companies did but the other remaining factors did not. In particular, the results showed that an increase in financial performance required ‘Economies of scale’, and that companies that concentrated on a small number of items, diversified products into four or more items, or owned two to four suppliers, reaped positive results in financial performance. Therefore, in addition to the selection and concentration of corporate management for production items and account management, applying strategies, like the inter-company M&A, consortiums and co-branded strategies to achieve ‘Economy of scale’, would highly enhance the financial performance of automotive parts suppliers.

Abstract
1. Introduction
    1.1. Research Background
2. Theoretical Background
    2.1. Automotive Assembly Company and PartsCooperation Company
    2.2. Company Size
    2.3. Business Diversification
    2.4. Experience in Overseas Market
3. Research Framework and Hypothesis
    3.1. Research Framework
    3.2. Research Hypothesis
4. Research Methodology
    4.1. Data
    4.2 Measurement of variables
5. Results
    5.1. Correlation Analysis
    5.2. Multi Regression Analysis
    5.3. Hypothesis Test Results
    5.4. Meaning and Interpretation of Variables byHypothesis
6. Conclusion and Implications
    6.1. Conclusion and Implications of the Study
    6.2. Limitations and Future Research
    References

• Ho-Jin AN(Graduate School of Management of Technology, Sogang University)
• Wan-Ki KIM(Graduate School of Management of Technology, Sogang University) Corresponding Author.