Family businesses are found in all economic segments, from small to huge sizes. Family-owned businesses can be the oldest form of business organization that plays a major role in the economic growth and development of this world and Indonesia. The family business has the potential to outperform other forms of business organizations through the synergy inherent between capital and management. In the family business, the existence of family participation in the company can strengthen family companies. Family involvement in business is very important because they are people who have a business and know business goals clearly than from others. The purpose of this research is to analyze the strategic plan on facing competitiveness at family firm UD Sinar Baja in Medan. The primary data is collected by using a quantitative method by surveying employees through a questionnaire. The results of data quality testing show that coefficient of correlation is 0.509, which shows moderate and positive correlation between Variable X (Strategic plan) and Variable (Competitiveness), and determination test shows that 26.0% of the competitiveness is affected by strategic plan in the business. Through the research, it is concluded that strategic plan has an positive impact with competitiveness which could increase the competitiveness of a company. The company that become the object of the research is UD Sinar Baja which located in Medan.