In this article, we analyzed the relation among wage gap, income distribution, and poverty in the labor market using the Korean welfare panel survey. According to the results of the analysis, the wage gap between men and women is decreasing as a result of cross-analysis, but the difference in education level, company size, and wage difference between regular and non-regular workers is increasing. In the case of a workplace with less than five people, the poverty experience rate is high. Dynamically, the proportion of both men and women who are self-employed with lower than middle school education has experienced a significant increase in long-term or repeated poverty. According to the company size, long-term poverty rate was 14.9% for men and 16.6% for women when the strength of the workplace was less than 5 for both men and women, and it was analyzed to be more vulnerable to poverty than other groups. Further, it was analyzed that a small business or small company was highly likely to experience poverty repeatedly. This result was the same even based on the income quintile. To improve the distribution due to the wage gap in the labor market, the same wage system for the same labor needs to be established. To reduce the difference in wages by company size, the government needs to develop policies and support to reduce the expenditure of workers in small businesses.